1,172 community and non-transient non-community water systems are listed for Montana in EPA SDWIS. 46 were sampled under UCMR 5; 5 of those had at least one PFAS result at or above the reporting level, and 2 had a highest single result at or above a 2024 EPA limit (PFOA or PFOS 4 ppt, or Hazard Index 1).
Montana map · Download: systems (CSV) · all results (CSV, gzip)
These are monitoring results collected under EPA's Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) at entry points, where treated water enters the distribution system; they are not tap-water samples. They are not compliance determinations: compliance with EPA's 2024 PFAS limits is judged on running annual averages of compliance monitoring, required from 2029, so a single UCMR 5 result at or above a limit is not a violation. “< MRL” means the compound was not quantified at EPA's minimum reporting level; it does not mean zero.
Sampled under UCMR 5 (46)
| System | PWSID | City | Population | Highest PFOA (ppt) | Highest PFOS (ppt) | Highest HI | Highest single result |
|---|---|---|---|---|---|---|---|
| Alpine Village Wua | MT0003229 | Columbia Falls | 125 | <MRL | 4.1 | 0 | PFOS 1–3 × its limit |
| Anaconda Water Department | MT0000016 | Anaconda | 6,750 | <MRL | <MRL | 0 | No PFAS detected |
| Belgrade City Of | MT0000136 | Belgrade | 10,460 | <MRL | <MRL | 0 | No PFAS detected |
| Big Pines Trailer Court | MT0000450 | Missoula | 78 | <MRL | <MRL | 0 | No PFAS detected |
| Big Sky County Water And Sewer Dist 363 | MT0002385 | Big Sky | 4,132 | <MRL | <MRL | 0.002 | Hazard Index below its limit |
| Bigfork County Water And Sewer | MT0000262 | Bigfork | 6,100 | <MRL | <MRL | 0 | No PFAS detected |
| Billings City Of | MT0000153 | Billings | 114,000 | <MRL | <MRL | 0 | No PFAS detected |
| Billings Heights Co Water Dist Of | MT0000155 | Billings | 12,000 | <MRL | <MRL | 0 | No PFAS detected |
| Black Rock Estates Subdivision | MT0004881 | Billings | 75 | <MRL | <MRL | 0 | No PFAS detected |
| Bozeman City Of | MT0000161 | Bozeman | 56,000 | <MRL | <MRL | 0 | No PFAS detected |
| Butte Silverbow Water Dept | MT0000170 | Butte | 33,000 | <MRL | <MRL | 0 | No PFAS detected |
| Columbia Falls City Of | MT0000181 | Columbia Falls | 4,450 | <MRL | <MRL | 0 | No PFAS detected |
| Culligan Water Conditioning Great Falls | MT0002630 | Great Falls | 900 | <MRL | <MRL | 0 | No PFAS detected |
| Dillon City Of | MT0000201 | Dillon | 4,300 | <MRL | <MRL | 0 | No PFAS detected |
| Fairfield Town Of | MT0000212 | Fairfield | 718 | <MRL | <MRL | 0 | No PFAS detected |
| Flathead County Water And Sewer | MT0001744 | Kalispell | 9,520 | <MRL | <MRL | 0 | No PFAS detected |
| Frenchtown High School | MT0000856 | Frenchtown | 550 | <MRL | <MRL | 0 | No PFAS detected |
| Glendive City Of | MT0000229 | Glendive | 4,873 | <MRL | <MRL | 0 | No PFAS detected |
| Great Falls City Of | MT0000525 | Great Falls | 60,000 | <MRL | <MRL | 0 | No PFAS detected |
| Hamilton City Of | MT0000234 | Hamilton | 5,660 | <MRL | <MRL | 0.002 | Hazard Index below its limit |
| Hardin City Of | MT0000235 | Hardin | 3,500 | <MRL | <MRL | 0 | No PFAS detected |
| Havre City Of | MT0000524 | Havre | 9,921 | <MRL | <MRL | 0 | No PFAS detected |
| Helena Water System | MT0000241 | Helena | 32,091 | <MRL | <MRL | 0 | No PFAS detected |
| Kalispell Public Works | MT0000259 | Kalispell | 25,000 | <MRL | 6.6 | 0.5 | PFOS 1–3 × its limit |
| Laurel Municipal Water System | MT0000270 | Laurel | 6,339 | <MRL | <MRL | 0 | No PFAS detected |
| Lewistown City Of | MT0000271 | Lewistown | 5,923 | <MRL | <MRL | 0 | No PFAS detected |
| Libby City Of | MT0000274 | Libby | 4,892 | <MRL | <MRL | 0 | No PFAS detected |
| Livingston City Of | MT0000573 | Livingston | 9,200 | <MRL | <MRL | 0 | No PFAS detected |
| Lockwood Water And Sewer District | MT0000156 | Billings | 5,900 | <MRL | <MRL | 0 | No PFAS detected |
| Malmstrom Air Force Base | MT0000515 | Malmstrom Air Force Base | 8,850 | <MRL | <MRL | 0 | Other PFAS detected |
| Miles City City Of | MT0000291 | Miles City | 9,565 | <MRL | <MRL | 0 | No PFAS detected |
| Missoula Water | MT0000294 | Missoula | 68,200 | <MRL | <MRL | 0 | No PFAS detected |
| Montana State University Billings | MT0004788 | Billings | 2,999 | <MRL | <MRL | 0 | No PFAS detected |
| Montana State University Bozeman | MT0004790 | Bozeman | 19,200 | <MRL | <MRL | 0 | No PFAS detected |
| Phantom Hills Water System | MT0004379 | Missoula | 810 | <MRL | <MRL | 0 | No PFAS detected |
| Pinesdale Town Of | MT0002926 | Pinesdale | 800 | <MRL | <MRL | 0 | No PFAS detected |
| Polson City Of | MT0000308 | Polson | 5,300 | <MRL | <MRL | 0 | No PFAS detected |
| River Rock County Water And Sewer Dist | MT0004082 | Belgrade | 4,200 | <MRL | <MRL | 0 | No PFAS detected |
| Rocky Mountain College | MT0004796 | Billings | 5,700 | <MRL | <MRL | 0 | No PFAS detected |
| Shelby City Of | MT0000328 | Shelby | 3,970 | <MRL | <MRL | 0 | No PFAS detected |
| Sidney City Of | MT0000330 | Sidney | 5,000 | <MRL | <MRL | 0 | No PFAS detected |
| Sun Prairie Village County | MT0000521 | Great Falls | 1,800 | <MRL | <MRL | 0 | No PFAS detected |
| Town Of Browning | 083090091 | Browning | 4,671 | <MRL | <MRL | 0 | No PFAS detected |
| University Of Montana | MT0004204 | Missoula | 15,000 | <MRL | <MRL | 0 | No PFAS detected |
| West Yellowstone Town Of | MT0003136 | West Yellowstone | 9,899 | <MRL | <MRL | 0 | No PFAS detected |
| Whitefish City Of | MT0000357 | Whitefish | 10,418 | <MRL | <MRL | 0 | No PFAS detected |
Not tested under UCMR 5 (1,126)
UCMR 5 required monitoring by systems serving 3,300 or more people and by a representative sample of smaller systems. The systems below have no UCMR 5 results in EPA's data. Not tested is not the same as not detected: the absence of results says nothing about PFAS in their water.
| System | PWSID | Type | City | Population | Counties |
|---|---|---|---|---|---|
| 2 Gramma'S House Day Care | MT0005067 | NTNCWS | Helena | 40 | Lewis and Clark County |
| 2727 West Central Duplexes | MT0000829 | CWS | Missoula | 35 | Missoula County |
| 99 Life Link Way | MT0004728 | NTNCWS | Alta | 60 | Gallatin County |
| Absaloka Mine | MT0000417 | NTNCWS | Billings | 80 | Big Horn County |
| Absarokee Water And Sewer Dist | MT0000003 | CWS | Absarokee | 1,100 | Stillwater County |
| Airport Industrial Building Unapproved | MT0005014 | NTNCWS | Missoula | 70 | Ravalli County |
| Alberton Town Of | MT0000015 | CWS | Alberton | 495 | Mineral County |
| Alder School | MT0004680 | NTNCWS | Alder | 30 | Madison County |
| Aldinger Acres Subdivision | MT0003552 | CWS | Billings | 100 | Yellowstone County |
| All West Business Park Lot 3 | MT0005197 | NTNCWS | Bozeman | 70 | Gallatin County |
| Alpine Mobile Manor | MT0000100 | CWS | Bigfork | 45 | Flathead County |
| Alpine Pacific Utilities | MT0004700 | CWS | Kalispell | 270 | Flathead County |
| American Water Technologies | MT0003688 | NTNCWS | Billings | 40 | Yellowstone County |
| Amity Square Water System | MT0003710 | CWS | Missoula | 50 | Missoula County |
| Amsterdam School District 75 | MT0001244 | NTNCWS | Manhattan | 179 | Gallatin County |
| Amsterdam Village Lots 11 & 12 Hoa | MT0005072 | NTNCWS | Manhattan | 268 | Gallatin County |
| Anaconda Ccc | MT0062254 | CWS | Anaconda | 290 | Deer Lodge County |
| Anderson School | MT0002084 | NTNCWS | Bozeman | 220 | Gallatin County |
| Anderson Steel Supply Inc | MT0004784 | NTNCWS | Great Falls | 55 | Cascade County |
| Andesite Ridge Water System | MT0004468 | CWS | Big Sky | 450 | Madison County |
| Angel Island Subdivision | MT0000582 | CWS | Troy | 150 | Lincoln County |
| Antelope County Water And Sewer | MT0003203 | CWS | Antelope | 59 | Sheridan County |
| Antigone Acres Hoa | MT0003003 | CWS | Hamilton | 85 | Ravalli County |
| Antler Ridge Homeowners Association | MT0004202 | CWS | Belgrade | 50 | Gallatin County |
| Ap Countryside Estates | MT0006000 | CWS | Kalispell | 93 | Flathead County |
| Ap Kookoosint | MT0004929 | CWS | Kalispell | 40 | Flathead County |
| Ap Williams | MT0001671 | CWS | Kalispell | 280 | Flathead County |
| Applegate Village | MT0004144 | CWS | Helena | 85 | Lewis and Clark County |
| Applied Materials | MT0003770 | NTNCWS | Kalispell | 150 | Flathead County |
| Aquatana | MT0003000 | NTNCWS | Havre | 25 | Hill County |
| Arlee | 083090027 | CWS | Pablo | 124 | Lake County |
| Arlee High School Dist No 8 | MT0000982 | NTNCWS | Arlee | 145 | Lake County |
| Arlee Junior High School | MT0003416 | NTNCWS | Arlee | 175 | Lake County |
| Arrow Creek Trailer Court | MT0004507 | CWS | Ballantine | 75 | Yellowstone County |
| Arrowhead School District No 75 | MT0001567 | NTNCWS | Pray | 120 | Park County |
| Ash Grove Cement Company | MT0001396 | NTNCWS | Clancy | 75 | Jefferson County |
| Ashland Community Water System | 083090061 | CWS | Lame Deer | 210 | Rosebud County |
| Ashland Water And Sewer District | MT0000458 | CWS | Ashland | 400 | Rosebud County |
| Ashley Hills Hoa | MT0004543 | CWS | Kalispell | 75 | Flathead County |
| Ashley Trails | MT0004945 | CWS | Kalispell | 27 | Flathead County |
| Aspen Knoll | MT0004367 | CWS | Kalispell | 75 | Flathead County |
| Assiniboine & Sioux Rural Water System | 083090050 | CWS | Poplar | 1,726 | Roosevelt County, Valley County |
| At Home Assisted Living | MT0003281 | NTNCWS | Missoula | 33 | Missoula County |
| Augusta School Dist 45 | MT0001429 | NTNCWS | Augusta | 86 | Lewis and Clark County |
| Avalon Subdivision | MT0004802 | CWS | Belgrade | 135 | Park County |
| Avista Utilities Noxon Rapids Dam | MT0000300 | CWS | Noxon | 43 | Sanders County |
| Ayers Hutterite Colony | MT0000413 | CWS | Grass Range | 58 | Fergus County |
| B & M Zoo Subdivision | MT0005006 | CWS | Missoula | 25 | Missoula County |
| Bahny Brae Subdivision | MT0003196 | CWS | East Helena | 35 | Lewis and Clark County |
| Bainville Town Of | MT0000020 | CWS | Bainville | 350 | Roosevelt County |
| Bair Clark Properties, Llc | MT0000374 | CWS | Missoula | 180 | Missoula County |
| Baker City Of | MT0000021 | CWS | Baker | 1,858 | Fallon County |
| Barnaby Lake Hoa | MT0003736 | CWS | Fortine | 75 | Lincoln County |
| Barnett Water Users System | MT0003183 | CWS | Helena | 70 | Lewis and Clark County |
| Basin County Water And Sewer Dist | MT0000014 | CWS | Basin | 200 | Jefferson County |
| Baxter Creek No 2 Hoa | MT0003323 | CWS | Belgrade | 450 | Gallatin County |
| Beacon Trailer Court Helena | MT0000596 | CWS | Helena | 55 | Lewis and Clark County |
| Bear Creek Village Bigfork | MT0000126 | CWS | Bigfork | 100 | Flathead County |
| Bearcreek Municipal Water Sys | MT0000063 | CWS | Red Lodge | 200 | Carbon County |
| Beartooth Spring Water | MT0005095 | NTNCWS | Billings | 25 | Carbon County |
| Beaverhead Jackson Water And Sewer Dist | MT0002590 | CWS | Jackson | 58 | Beaverhead County |
| Bedrockbabb Water System | 083090004 | CWS | Browning | 645 | Glacier County |
| Bee Hive Homes Msla | MT0004891 | CWS | Missoula | 106 | Missoula County |
| Bee Hive Homes Of Dillon | MT0005003 | NTNCWS | Whitehall | 47 | Beaverhead County |
| Belfry Carbon Co Water And Sewer Dist | MT0000460 | CWS | Belfy | 205 | Carbon County |
| Belgrade Commercial Park Pws | MT0004958 | NTNCWS | Belgrade | 50 | Gallatin County |
| Belgrade Trailer Court | MT0002696 | CWS | Bozeman | 50 | Gallatin County |
| Belt Town Of | MT0000138 | CWS | Belt | 600 | Cascade County |
| Bequet Confections | MT0005019 | NTNCWS | Bozeman | 29 | Gallatin County |
| Best View Estates | MT0005080 | CWS | Somers | 50 | Flathead County |
| Big Arm Water System | 083090309 | CWS | Pablo | 116 | Lake County |
| Big Bend Ranch Subdivision | MT0004261 | CWS | Great Falls | 100 | Cascade County |
| Big Mountain Water Company | MT0000060 | CWS | Whitefish | 2,435 | Flathead County |
| Big Rose Colony | MT0004833 | CWS | Shelby | 75 | Toole County |
| Big Sandy Town Of | MT0000150 | CWS | Big Sandy | 608 | Chouteau County |
| Big Sky Colony Cut Bank | MT0001647 | CWS | Cut Bank | 107 | Glacier County |
| Big Sky Mobile Home Park | MT0004683 | CWS | Great Falls | 40 | Cascade County |
| Big Sky Mobile Manor | MT0002493 | CWS | Columbia Falls | 35 | Flathead County |
| Big Sky School District No 72 | MT0001281 | NTNCWS | Big Sky | 275 | Gallatin County |
| Big Sky Sd Ophir Elementary School | MT0004861 | NTNCWS | Big Sky | 175 | Gallatin County |
| Big Sky Trailer Ct Hamilton | MT0000504 | CWS | Hamilton | 70 | Ravalli County |
| Big Spur Tr Ct | MT0001599 | CWS | Hermosa Beach | 65 | Park County |
| Big Stack Estates | MT0004682 | CWS | Helena | 60 | Cascade County |
| Big Stone Colony Inc | MT0003077 | CWS | Sand Coulee | 130 | Cascade County |
| Big Timber City Of | MT0000463 | CWS | Big Timber | 1,650 | Sweet Grass County |
| Big Valley Water Inc | MT0003971 | NTNCWS | Glasgow | 200 | Valley County |
| Billings Christian High School | MT0004584 | NTNCWS | Billings | 125 | Yellowstone County |
| Billings Christian Schools | MT0003654 | NTNCWS | Billings | 130 | Yellowstone County |
| Billings Peterbilt | MT0004829 | NTNCWS | Billings | 60 | Yellowstone County |
| Birch Creek Colony | MT0001781 | CWS | Valier | 120 | Pondera County |
| Birchwood Duplexes | MT0002537 | CWS | Missoula | 43 | Missoula County |
| Birney Village | 083090062 | CWS | Lame Deer | 96 | Rosebud County |
| Bissell School District No 58 | MT0000923 | NTNCWS | Kalispell | 97 | Flathead County |
| Bitterroot Gateway Mb Pk Lolo | MT0000443 | CWS | Lolo | 130 | Missoula County |
| Bitterroot Health Stevensville | MT0005128 | NTNCWS | Missoula | 140 | Ravalli County |
| Bitterroot Meadows Hoa Lolo | MT0003146 | CWS | Lolo | 120 | Missoula County |
| Bitterroot Pines Tr Ct Florence | MT0002128 | CWS | Hamilton | 45 | Ravalli County |
| Bitterroot Tp Havre Unapproved | MT0003404 | CWS | Havre | 88 | Hill County |
| Black Eagle Cascade County Water Sewer | MT0000157 | CWS | Black Eagle | 1,233 | Cascade County |
| Blackfeet Community Hospital | 083090092 | NTNCWS | Browning | 600 | |
| Blackfeet Dorm. Water System | 083090002 | CWS | Browning | 66 | |
| Blackfoot Water System | 083090003 | CWS | Browning | 56 | Glacier County |
| Blanchard Hollow Estates Wua | MT0003219 | CWS | Whitefish | 53 | Flathead County |
| Blue Cloud Subdivision | MT0004288 | CWS | Helena | 60 | Lewis and Clark County |
| Blue Creek School Dist 3 | MT0001712 | NTNCWS | Billings | 198 | Yellowstone County |
| Blue Grass Water Users Association | MT0004093 | CWS | Billings | 60 | Yellowstone County |
| Blue Mountain Trailer Ct | MT0000381 | CWS | Missoula | 75 | Missoula County |
| Blue Sky Heights Wua Clancy | MT0000030 | CWS | Clancy | 250 | Jefferson County |
| Bluebird Mb Hm Park Hamilton | MT0001083 | CWS | Anaconda | 75 | Ravalli County |
| Blunderbuss | MT0005090 | NTNCWS | Bozeman | 25 | Gallatin County |
| Bmp Lincoln Rentals Llc | MT0002548 | CWS | Bozeman | 31 | Gallatin County |
| Bobs Valley Service Inc | MT0003662 | NTNCWS | East Helena | 1,032 | Lewis and Clark County |
| Bolin Elementary School Dist 5 | MT0001620 | NTNCWS | Terry | 45 | Prairie County |
| Bonner Housing Pws System | MT0000467 | CWS | Missoula | 128 | Missoula County |
| Bonner Millsite Pws | MT0002465 | NTNCWS | Missoula | 60 | Missoula County |
| Bonner School District No 14 | MT0000846 | NTNCWS | Bonner | 420 | Missoula County |
| Bonnie'S Place Inc | MT0004074 | CWS | Missoula | 60 | Missoula County |
| Boulder City Of | MT0000158 | CWS | Boulder | 1,400 | Jefferson County |
| Box Elder School District 13G | MT0002521 | NTNCWS | Box Elder | 500 | Hill County |
| Bozeman Fish Technology Ctr | MT0003803 | NTNCWS | Bozeman | 75 | Gallatin County |
| Brady County Water Sewer District | MT0000164 | CWS | Brady | 144 | Pondera County |
| Branco Court | MT0004568 | CWS | Missoula | 37 | Missoula County |
| Bridge Creek Estates Subdivision | MT0004555 | CWS | Helena | 205 | Lewis and Clark County |
| Bridger Town Of | MT0000165 | CWS | Bridger | 750 | Carbon County |
| Bridger Base Water System | MT0004931 | CWS | Belgrade | 75 | Gallatin County |
| Bridger Brewing Three Forks | MT0005117 | NTNCWS | Three Forks | 470 | Broadwater County |
| Bridger Pines County W And S District | MT0001787 | CWS | Bozeman | 58 | Gallatin County |
| Broadus Town Of | MT0000166 | CWS | Broadus | 450 | Powder River County |
| Broadview Town Of | MT0000167 | CWS | Broadview | 200 | Yellowstone County |
| Broadwater Estates Hoa | MT0004697 | CWS | East Helena | 40 | Lewis and Clark County |
| Brockton, Town Of | 083090057 | CWS | Wolf Point | 375 | Roosevelt County |
| Brook Drive Water Assn | MT0000099 | CWS | Kalispell | 32 | Flathead County |
| Bruckner Truck And Equipment | MT0003934 | NTNCWS | Missoula | 125 | Missoula County |
| Bryant No 3 Subdivision | MT0004489 | CWS | Helena | 100 | Lewis and Clark County |
| Bucks T4 | MT0001292 | NTNCWS | Big Sky | 153 | Gallatin County |
| Buena Vista Community, Inc | MT0000378 | CWS | Missoula | 90 | Missoula County |
| Buffalo Mountain Subdivision | MT0005038 | CWS | Bigfork | 90 | Flathead County |
| Buffalo Ranch Water Company | MT0004047 | CWS | Pray | 33 | Park County |
| Busby Community Water System | 083090063 | CWS | Lame Deer | 535 | Big Horn County |
| Bushard Water Company | MT0005164 | CWS | Black Eagle | 425 | Cascade County |
| Buzz Inn | MT0000592 | CWS | East Helena | 95 | Lewis and Clark County |
| Bynum - Teton Co W & S District | MT0004778 | CWS | Bynum | 100 | Teton County |
| C & C Community Inc | MT0005017 | CWS | Billings | 145 | Yellowstone County |
| C And D Hoa | MT0003283 | CWS | Missoula | 140 | Missoula County |
| C Bar N Camp | MT0002973 | NTNCWS | Augusta | 110 | Lewis and Clark County |
| Cabinet Ranger Station | MT0062359 | NTNCWS | Trout Creek | 145 | Sanders County |
| Camel Mountain Hoa | MT0000572 | CWS | Helena | 96 | Lewis and Clark County |
| Camelot Hoa | MT0000615 | CWS | Helena | 96 | Lewis and Clark County |
| Camp Creek Wua Inc | MT0004378 | CWS | Malta | 50 | Phillips County |
| Camrose Colony | MT0004036 | CWS | Ledger | 95 | Toole County |
| Canoe Gulch Ranger Station | MT0062355 | NTNCWS | Libby | 64 | Lincoln County |
| Canyon Creek School District 4 | MT0001724 | NTNCWS | Billings | 200 | Yellowstone County |
| Canyon Ferry Road Baptist Church | MT0004527 | NTNCWS | East Helena | 292 | Lewis and Clark County |
| Canyon Pines Hoa | MT0002119 | CWS | Missoula | 32 | Missoula County |
| Canyon Ranches Subdivision | MT0005229 | CWS | Red Lodge | 36 | Carbon County |
| Cardwell School Dist 16 And 31 | MT0001398 | NTNCWS | Cardwell | 63 | Jefferson County, Madison County |
| Carols Trailer Court | MT0000451 | CWS | Missoula | 50 | Missoula County |
| Carpenter Lake Hoa | MT0003694 | CWS | Eureka | 65 | Lincoln County |
| Carter Chouteau Co Water Dist | MT0000520 | CWS | Carter | 150 | Chouteau County |
| Cascade Town Of | MT0000171 | CWS | Cascade | 650 | Cascade County |
| Cascade Colony | MT0001738 | CWS | Sun River | 105 | Cascade County |
| Casitas Del Mesa Mhp | MT0002738 | CWS | Glendive | 180 | Dawson County |
| Casitas Del Rio | MT0005060 | CWS | Houston | 216 | Dawson County |
| Catlin Street Mobile Court | MT0003538 | CWS | Missoula | 35 | Missoula County |
| Cayuse Prairie School Dist No 10 | MT0000896 | NTNCWS | Kalispell | 195 | Flathead County |
| Centennial Homeowner'S Association, Inc | MT0004438 | CWS | Corvallis | 115 | Ravalli County |
| Centerville School | MT0000771 | NTNCWS | Sand Coulee | 292 | Cascade County |
| Central Water Conditioning | MT0004502 | NTNCWS | Sidney | 50 | Richland County |
| Chautauqua Terrace Hoa | MT0003141 | CWS | Lakeside | 55 | Flathead County |
| Cherry Creek Estates Llc | MT0004392 | CWS | Bilings | 600 | Yellowstone County |
| Cherry Creek Wua Glasgow | MT0000228 | CWS | Glasgow | 180 | Valley County |
| Cherry View | MT0004856 | CWS | Lakeside | 352 | Flathead County |
| Chester Town Of | MT0000173 | CWS | Chester | 870 | Liberty County |
| Chico Hot Springs | MT0001564 | NTNCWS | Pray | 415 | Park County |
| Chief Martin Charlo Homesite | 083090305 | CWS | Pablo | 66 | Lake County |
| Chinook City Of | MT0000174 | CWS | Chinook | 1,300 | Blaine County |
| Choteau City Of | MT0000175 | CWS | Choteau | 1,691 | Teton County |
| Christ Church Of Great Falls | MT0004847 | NTNCWS | Great Falls | 85 | Cascade County |
| Christian Childrens Ranch | MT0003720 | CWS | St Ignatius | 65 | Lake County |
| Christian Life Center | MT0003865 | NTNCWS | Missoula | 846 | Missoula County |
| Church Of Christ | MT0004265 | NTNCWS | Billings | 30 | Yellowstone County |
| Churchill North Subdivision | MT0004431 | CWS | Manhattan | 155 | Gallatin County |
| Churchill Retirement Home | MT0001375 | CWS | Manhattan Mt | 80 | Gallatin County |
| Cinnabar The | MT0001557 | CWS | Gardiner | 175 | Park County |
| Circle Town Of | MT0000176 | CWS | Circle | 644 | McCone County |
| Circle H Water Inc | MT0004446 | CWS | Missoula | 215 | Missoula County |
| Circle J Trailer Court | MT0000452 | CWS | Missoula | 59 | Missoula County |
| City Lights Comm Subdi | MT0004727 | NTNCWS | East Helena | 55 | Jefferson County |
| Clancy Elementary School Dist #1 | MT0001397 | NTNCWS | Clancy | 333 | Jefferson County |
| Clarice Paul Water System | 083090021 | CWS | Pablo | 35 | Lake County |
| Clarks Lookout | MT0004249 | CWS | Dillon | 62 | Beaverhead County |
| Clear View Academy | MT0004536 | CWS | Heron | 70 | Sanders County |
| Clear View Horizon Academy Unapproved | MT0004965 | NTNCWS | Heron | 32 | Sanders County |
| Clearview Heights Lake County Water Dist | MT0003233 | CWS | Polson | 90 | Lake County |
| Clinton School | MT0000824 | NTNCWS | Clinton | 250 | Missoula County |
| Clyde Park Water Dept | MT0000178 | CWS | Clyde Park | 300 | Park County |
| Cmrwa Musselshell Judith Rural Water Sys | MT0005109 | CWS | Lewistown | 100 | Wheatland County |
| Cobblestone Court | MT0004831 | CWS | Great Falls | 50 | Cascade County |
| Cobblestone Subdivision | MT0004572 | CWS | Bozeman | 150 | Gallatin County |
| College Of Technology West Campus | MT0003506 | NTNCWS | Missoula | 140 | Missoula County |
| Colstrip City Of | MT0000180 | CWS | Colstrip | 2,350 | Rosebud County |
| Columbia Range Hoa | MT0004818 | CWS | Columbia Falls | 47 | Flathead County |
| Columbus Town Of | MT0000185 | CWS | Columbus | 1,900 | Stillwater County |
| Comstock | MT0004656 | NTNCWS | Tampa | 330 | Lincoln County |
| Conrad Water Dept | MT0000186 | CWS | Conrad | 2,500 | Pondera County |
| Consolidated Charlo Lake Co W And S Dist | MT0000172 | CWS | Charlo | 450 | Lake County |
| Convergence Ministries | MT0003877 | NTNCWS | Missoula | 130 | Missoula County |
| Cooke City Water District | MT0000187 | CWS | Bozeman | 300 | Park County |
| Cool Spring Colony | MT0004051 | CWS | Rudyard | 75 | Hill County |
| Cooney Enterprises | MT0003670 | CWS | Bozeman | 50 | Carbon County |
| Cop Construction Llc | MT0004574 | NTNCWS | Billings | 30 | Yellowstone County |
| Coram County Water And Sewer District | MT0000189 | CWS | Coram | 450 | Flathead County |
| Corvallis Gym And Middle School | MT0004041 | NTNCWS | Corvallis | 900 | Ravalli County |
| Corvallis Mobile Village | MT0002799 | CWS | Coeur D'Alene | 138 | Ravalli County |
| Corvallis Primary School | MT0003257 | NTNCWS | Corvallis | 450 | Ravalli County |
| Corvallis Sd Rise Charter Campus | MT0004499 | NTNCWS | Corvallis | 75 | Ravalli County |
| Cottonwood Estates | MT0004006 | CWS | Greycliff | 50 | Sweet Grass County |
| Cottonwood Homes | MT0004626 | CWS | Kalispell | 45 | Flathead County |
| Cougar Meadows | MT0004345 | CWS | St Regis | 45 | Mineral County |
| Cougar Park Industrial | MT0005182 | NTNCWS | Bozeman | 25 | Gallatin County |
| Country Bourne | MT0004597 | CWS | Kalispell | 25 | Flathead County |
| Country Court Gallatin | MT0001644 | CWS | Bozeman | 30 | Gallatin County |
| Country Court Community Inc | MT0002819 | CWS | Kalispell | 25 | Flathead County |
| Country Estates Mble Home Park | MT0001892 | CWS | Columbia Falls | 125 | Flathead County |
| Country Estates Water Supply | MT0002846 | CWS | Kalispell | 490 | Flathead County |
| Country Haven Estates Whispering Pines | MT0004376 | CWS | Belgrade | 100 | Stillwater County |
| Country Lake Homes Whitefish | MT0003031 | CWS | Kalispell | 260 | Flathead County |
| Countryside Court Missoula | MT0000376 | CWS | Missoula | 37 | Missoula County |
| Countryside Village Mhp Grt Fls | MT0004830 | CWS | Orem | 600 | Cascade County |
| Covered Wagon Mb Hm Park | MT0003810 | CWS | Lincoln | 500 | Gallatin County |
| Crane Mountain Estates | MT0004884 | CWS | Bigfork | 50 | Lake County |
| Crazy Mountain Ranch Employee Housing | MT0004667 | NTNCWS | Clyde Park | 80 | Park County |
| Creekside Motel Rv And Trlr Pk | MT0000530 | CWS | Eureka | 35 | Lincoln County |
| Creston Center | MT0004246 | NTNCWS | Kalispell | 80 | Flathead County |
| Creston School District 9 | MT0000933 | NTNCWS | Kalispell | 121 | Flathead County |
| Cross Point Community Church | MT0003870 | NTNCWS | Missoula | 180 | Missoula County |
| Crow Agency Water System | 083090011 | CWS | Crow Agency | 2,057 | Big Horn County |
| Crystal Lake Subdivision Hoa | MT0001145 | CWS | Fortine | 34 | Lincoln County |
| Crystal Springs Water System | MT0003986 | CWS | Billings | 225 | Yellowstone County |
| Cskt Division Of Fire Management | 083090320 | NTNCWS | Pablo | 190 | |
| Culbertson Town Of | MT0000192 | CWS | Culbertson | 714 | Roosevelt County |
| Culligan Bottled Water Kalispell | MT0003302 | NTNCWS | Kalispell | 125 | Flathead County |
| Culligan Of Missoula | MT0004067 | NTNCWS | Missoula | 320 | Missoula County |
| Culligan Water Facility Butte | MT0003960 | NTNCWS | Butte | 423 | Silver Bow County |
| Curious Minds Montessori Preschool | MT0005044 | NTNCWS | Hamilton | 205 | Ravalli County |
| Custer Co Water And Sewer Dist | MT0003041 | CWS | Miles City | 480 | Custer County, Yellowstone County |
| Custer School Dist No 15 | MT0001748 | NTNCWS | Custer | 100 | Yellowstone County |
| Cut Bank City Of | MT0000193 | CWS | Cut Bank | 3,105 | Glacier County |
| Cut Bank North Water District | MT0000619 | CWS | Cut Bank | 478 | Glacier County |
| Dailys Premium Meats | MT0000825 | NTNCWS | Missoula | 100 | Missoula County |
| Dakota Valley Mobile Home Park | MT0004562 | CWS | Kodak | 75 | Lewis and Clark County |
| Daly Estates Subdivision | MT0004517 | CWS | Hamilton | 123 | Ravalli County |
| Darby Town Of | MT0000195 | CWS | Darby | 850 | Ravalli County |
| Davis Meadow Village | MT0003990 | CWS | East Helena | 180 | Lewis and Clark County |
| Dayton School | 083090302 | NTNCWS | East Polson | 74 | |
| Dayton Water System | 083090022 | CWS | Pablo | 25 | Lake County |
| Deer Lick Subdivision Water District | MT0004583 | CWS | Haugan | 70 | Mineral County |
| Deer Lodge City Of | MT0000197 | CWS | Deer Lodge | 2,900 | Powell County |
| Deer Park School District 2 | MT0000910 | NTNCWS | Columbia Falls | 80 | Flathead County |
| Deerfield Hutterite Colony | MT0000431 | CWS | Lewistown | 51 | Fergus County |
| Denton Town Of | MT0000199 | CWS | Denton | 255 | Fergus County |
| Designs For Health Inc | MT0003791 | NTNCWS | Arlee | 82 | Lake County |
| Devon Water Inc | MT0000200 | CWS | Shelby | 75 | Toole County |
| Discovery Kid Zone Montessori | MT0005024 | NTNCWS | East Helena | 110 | Jefferson County |
| District Court Llc | MT0002651 | CWS | Kalispell | 50 | Flathead County |
| Dixon (Old Agency) | 083090023 | CWS | Pablo | 72 | Sanders County |
| Dixon, Town Of | 083090034 | CWS | Pablo | 200 | Sanders County |
| Dodson Town Of | MT0000203 | CWS | Dodson | 120 | Phillips County |
| Double Diamond Subdivision Arbor Hills | MT0004845 | CWS | Billings | 50 | Yellowstone County |
| Drummond Elementary School 2 | MT0003280 | NTNCWS | Drummond | 191 | Granite County |
| Drummond High School 1 | MT0000686 | NTNCWS | Drummond | 191 | Granite County |
| Dry Prairie Rural Water Authority | MT0004348 | CWS | Culbertson | 3,005 | Roosevelt County |
| Dry Redwater Regional Water Authority | MT0004839 | CWS | Circle | 365 | McCone County |
| Duck Creek Mobile Home Park | MT0001786 | CWS | Billings | 70 | Yellowstone County |
| Duncan Ranch Colony | MT0000418 | CWS | Harlowton | 96 | Wheatland County |
| Dutton Town Of | MT0000204 | CWS | Dutton | 338 | Teton County |
| Dwaynes Village | MT0004745 | CWS | Kalispell | 63 | Flathead County |
| Dyksterhouse Well Users Assoc | MT0004598 | CWS | Manhattan | 28 | Gallatin County |
| Dynojet Research | MT0004385 | NTNCWS | Belgrade | 25 | Gallatin County |
| Eagle Creek Colony | MT0003152 | CWS | Galata | 125 | Liberty County |
| Eagle Fjord | MT0004990 | NTNCWS | Bozeman | 55 | Gallatin County |
| Eagle Mountain Rural Pws | MT0004461 | CWS | Columbus | 50 | Stillwater County |
| Eagle Ridge Estates Co W And S Dist | MT0004475 | CWS | Kalispell | 115 | Flathead County |
| Eagleman Community Water | 083090074 | CWS | Box Elder | 400 | Hill County |
| Earth Elements Unapproved | MT0005023 | NTNCWS | Gallatin Gateway | 57 | Gallatin County |
| East Decker Coal Mine | MT0000953 | NTNCWS | Decker | 28 | Big Horn County |
| East End Colony Inc | MT0001780 | CWS | Havre | 100 | Hill County |
| East Evergreen Mobile Manor | MT0004753 | CWS | Kalispell | 155 | Flathead County |
| East Gate Work Camp | MT0003440 | CWS | Gardiner | 208 | Park County |
| East Helena City Of | MT0000196 | CWS | East Helena | 2,114 | Lewis and Clark County |
| East Malta Colony | MT0001769 | CWS | Malta | 47 | Phillips County |
| East Valley Estates | MT0004514 | CWS | Kalispell | 63 | Flathead County |
| East View Acres Water System | MT0003565 | CWS | Missoula | 25 | Missoula County |
| East Wood Village Trailer Park | MT0002814 | CWS | Columbia Falls | 36 | Flathead County |
| Eastgate School District 09 | MT0003200 | NTNCWS | East Helena | 342 | Lewis and Clark County |
| Eastgate Village Sewer And Water | MT0001784 | CWS | East Helena | 2,000 | Lewis and Clark County |
| Eastwood Mobile Home Court | MT0005147 | CWS | Dallas | 140 | Yellowstone County |
| Edannes Mobile Home Park | MT0000039 | CWS | Hermosa Beach | 55 | Park County |
| Ekalaka Town Of | MT0000206 | CWS | Ekalaka | 400 | Carter County |
| El Mar Estates Msla Co Water | MT0000517 | CWS | Missoula | 1,350 | Missoula County |
| Elder Grove Middle School Bldg 6 | MT0005057 | NTNCWS | Billings | 600 | Yellowstone County |
| Elder Grove School Building Five | MT0004089 | NTNCWS | Billings | 200 | Yellowstone County |
| Elder Grove School Buildings 1 & 2 | MT0003620 | NTNCWS | Billings | 420 | Yellowstone County |
| Elevate Church | MT0004148 | NTNCWS | Missoula | 206 | Missoula County |
| Elevation Newco, Llc | MT0002154 | NTNCWS | Dillon | 40 | Beaverhead County |
| Elk Creek Colony | MT0004739 | CWS | Augusta | 84 | Lewis and Clark County |
| Elk Grove Water | MT0004248 | CWS | Bozeman | 672 | Gallatin County |
| Elk Meadows Ranchettes | MT0000632 | CWS | Missoula | 175 | Missoula County |
| Elk Park Village | MT0002856 | CWS | Columbia Falls | 35 | Flathead County |
| Elkhorn Health And Rehabilitation Llc | MT0000618 | CWS | Clancy | 89 | Jefferson County |
| Elmo Water System | 083090024 | CWS | Pablo | 220 | Lake County |
| Emerald Heights Hoa Water & Sewer Dist | MT0002862 | CWS | Whitefish | 70 | Flathead County |
| Emerald View Park | MT0002996 | CWS | Billings | 320 | Yellowstone County |
| Emkayan Village Co Water And Sewer Dist | MT0000540 | CWS | Libby | 160 | Lincoln County |
| Encampment Trail | MT0004916 | CWS | Big Sky | 100 | Madison County |
| Ennis Town Of | MT0000208 | CWS | Ennis | 1,400 | Madison County |
| Ennis Hot Springs Business Park Inc | MT0004384 | NTNCWS | Mcallister | 216 | Madison County |
| Estates At Yellowstone Llc | MT0000464 | CWS | Boca Raton | 800 | Yellowstone County |
| Ethridge County Water District | MT0004353 | CWS | Ethridge | 70 | Toole County |
| Eureka Town Of | MT0000210 | CWS | Eureka | 1,995 | Lincoln County |
| Eureka Ranger Station | MT0062342 | NTNCWS | Eureka | 127 | Lincoln County |
| Evaro Water System | 083090025 | CWS | Pablo | 40 | Missoula County |
| Evergreen Subdivision | MT0004466 | CWS | Joliet | 45 | Carbon County |
| F H Stoltze Land And Lumber Co | MT0000911 | NTNCWS | Columbia Falls | 105 | Flathead County |
| Fairfield Mennonite Church | MT0004994 | NTNCWS | Fairfield | 260 | Cascade County, Teton County |
| Fairhaven Colony | MT0001773 | CWS | Ulm | 105 | Cascade County |
| Fairmont Egan School Dist No 3 | MT0000931 | NTNCWS | Kalispell | 200 | Flathead County |
| Fairmont Hot Springs Resort | MT0000589 | CWS | Anaconda | 1,965 | Silver Bow County |
| Fairview Town Of | MT0000213 | CWS | Fairview | 1,000 | Richland County |
| Fallon County Water District | MT0003035 | CWS | Baker | 85 | Fallon County |
| Farm To Market Store | MT0005138 | NTNCWS | Libby | 274 | Lincoln County |
| Fedex Relay Center | MT0005207 | NTNCWS | Billings | 74 | Yellowstone County |
| Fieldstone Subdivision | MT0004635 | CWS | Kalispell | 52 | Flathead County |
| Firelight Meadows Llc | MT0004236 | CWS | Bozeman | 350 | Gallatin County |
| First Student Inc | MT0003107 | NTNCWS | Knoxville | 130 | Yellowstone County |
| Fish Wildlife And Parks R2 Headquarters | MT0043464 | NTNCWS | Missoula | 35 | Missoula County |
| Fisher Water Service | MT0001848 | CWS | Billings | 750 | Yellowstone County |
| Fishermans Village Subdivision | MT0004722 | CWS | West Yellowstone | 25 | Gallatin County |
| Flathead Co Water District No 8 | MT0000261 | CWS | Columbia Falls | 475 | Flathead County |
| Flathead County Water Dist 101 | MT0000184 | CWS | Columbia Falls | 210 | Flathead County |
| Flathead Lake Biological Station U Of M | MT0003724 | NTNCWS | Polson | 66 | Flathead County, Lake County |
| Flathead Lake Lodge | MT0000903 | NTNCWS | Bigfork | 205 | Flathead County |
| Flaxville Town Of | MT0000549 | CWS | Flaxville | 82 | Daniels County |
| Florence Carlton School | MT0001054 | NTNCWS | Florence | 1,025 | Ravalli County |
| Flthd Cty Road Maintenance Shop | MT0004109 | NTNCWS | Kalispell | 66 | Flathead County |
| Forest Acres Tr Pk Whitefish | MT0000064 | CWS | Whitefish | 390 | Flathead County |
| Forest Creek Subd | MT0002074 | CWS | Bozeman | 45 | Gallatin County |
| Forest Hill Hoa | MT0001785 | CWS | Kalispell | 50 | Flathead County |
| Forest Inn Lounge And Apartments | MT0000840 | CWS | Missoula | 130 | Missoula County |
| Forest Park Tr Ct No 1 Bozeman | MT0001366 | CWS | Eagle | 260 | Gallatin County |
| Forest Park Water Rsid 24 | MT0000233 | CWS | Glendive | 1,200 | Dawson County |
| Forest Park Water Users Association | MT0000591 | CWS | Clancy | 323 | Jefferson County |
| Forest River Mobile Home And Rv Park | MT0004809 | CWS | Kalispell | 90 | Flathead County |
| Forest View Hoa | MT0003594 | CWS | Florence | 65 | Ravalli County |
| Forsyth City Of | MT0000215 | CWS | Forsyth | 2,260 | Rosebud County |
| Fort Belknap Agency Water System | 083090041 | CWS | Harlem | 2,600 | Blaine County |
| Fort Benton City Of | MT0000216 | CWS | Fort Benton | 1,500 | Chouteau County |
| Fort Harrison Military Complex | MT0004736 | NTNCWS | Fort Harrison | 580 | Lewis and Clark County |
| Fort Kipp Subdivision Water System | 083090052 | CWS | Wolf Point | 130 | Roosevelt County |
| Fort Peck Rural County Water District | MT0004177 | CWS | Ft. Peck | 663 | Valley County |
| Fort Peck Town Of | MT0000218 | CWS | Fort Peck | 240 | Valley County |
| Fort Smith Water And Sewer District | MT0004765 | CWS | Worden | 450 | Big Horn County |
| Fortine School District 14 | MT0001146 | NTNCWS | Fortine | 98 | Lincoln County |
| Fosters Country View Tr Pk Llc | MT0000429 | CWS | Kalispell | 50 | Flathead County |
| Four Corners Business Park | MT0002903 | NTNCWS | Bozeman | 200 | Gallatin County |
| Fox Hill Estates | MT0004458 | CWS | Kalispell | 163 | Flathead County |
| Fox Water Service Incorporated | MT0002895 | CWS | Laurel | 250 | Yellowstone County |
| Foys Lakeside Estates Water & Sewer Dist | MT0004150 | CWS | Kalispell | 36 | Flathead County |
| Franklin Hills Subdivision | MT0004734 | CWS | Bozeman | 50 | Gallatin County |
| Frazer Water System | 083090053 | CWS | Wolf Point | 452 | Valley County |
| Frenchtown Elementary School Dist 40 | MT0002536 | NTNCWS | Frenchtown | 700 | Missoula County |
| Frenchtown Valley View Tr Ct | MT0000404 | CWS | Missoula | 50 | Missoula County |
| Froid Town Of | MT0000221 | CWS | Froid | 450 | Roosevelt County |
| Fromberg Town Of | MT0000222 | CWS | Fromberg | 498 | Carbon County |
| Galata County Water District | MT0000009 | CWS | Galata | 200 | Liberty County, Toole County |
| Galen Facility | MT0000223 | CWS | Butte | 90 | Deer Lodge County |
| Gallatin Gateway Inn | MT0000638 | NTNCWS | Big Sky | 375 | Gallatin County |
| Gallatin Gateway School Dist 35 | MT0001288 | NTNCWS | Gallatin Gateway | 202 | Gallatin County |
| Gallatin River Apartments | MT0001891 | CWS | Townsend | 40 | Gallatin County |
| Gallatin Village Mob Hm Park | MT0000627 | CWS | Bozeman | 100 | Gallatin County |
| Garden Center Subdivision Owners Assoc | MT0003953 | NTNCWS | Manhattan | 150 | Gallatin County |
| Gardiner Park Co Water Dist | MT0000224 | CWS | Gardiner | 700 | Park County |
| Garnet Usa | MT0004918 | NTNCWS | Alder | 45 | Madison County |
| Gateway Village System 2 | MT0005027 | CWS | Big Sky | 68 | Gallatin County |
| Gateway Village System 3 | MT0005028 | CWS | Big Sky | 68 | Gallatin County |
| Gateway Village System 4 | MT0005029 | CWS | Big Sky | 60 | Gallatin County |
| Gateway Village System 5 | MT0005030 | CWS | Big Sky | 70 | Gallatin County |
| Gateway Village System 7 | MT0005032 | CWS | Big Sky | 77 | Gallatin County |
| Gcc Trident Llc | MT0000346 | NTNCWS | Three Forks | 75 | Gallatin County |
| Genesis Business Park | MT0004178 | CWS | Bozeman | 670 | Gallatin County |
| Geraldine Town Of | MT0000225 | CWS | Geraldine | 260 | Chouteau County |
| Geyser Judith Basin Cty Water Sewer Dist | MT0000226 | CWS | Geyser | 125 | Judith Basin County |
| Gildford Colony | MT0001770 | CWS | Gildford | 70 | Hill County |
| Glacier Colony | MT0000566 | CWS | Cut Bank | 80 | Glacier County |
| Glacier Park International Airport | MT0000929 | NTNCWS | Kalispell | 2,680 | Flathead County |
| Glacier Point Ho And Wua | MT0004559 | CWS | Helena | 210 | Lewis and Clark County |
| Glacier View School | 083090321 | NTNCWS | Ronan | 265 | |
| Glasgow City Of | MT0000415 | CWS | Glasgow | 3,253 | Valley County |
| Glendale Colony | MT0001648 | CWS | Cut Bank | 150 | Glacier County |
| Glendive Alliance Church | MT0003977 | NTNCWS | Glendive | 200 | Dawson County |
| Glessner Trailer Court | MT0000405 | CWS | Missoula | 67 | Missoula County |
| Go 2 U Water Delivery | MT0004754 | CWS | Laurel | 875 | Yellowstone County |
| Godfrey Canyon Estates | MT0002398 | CWS | Manhattan | 100 | Gallatin County |
| Golden Age Village | MT0003313 | CWS | Emigrant | 180 | Park County |
| Golden Eagle Water Users Assn | MT0002840 | CWS | Billings | 125 | Yellowstone County |
| Golden Estates Homeowners Association | MT0004187 | CWS | East Helena | 400 | Lewis and Clark County |
| Golden Estates Trailer Court | MT0000597 | CWS | Kodak | 225 | Lewis and Clark County |
| Golden Meadows Subdivision | MT0005141 | CWS | Dallas | 772 | Yellowstone County |
| Golden Meadows Subdivision 2Nd Cc | MT0005186 | CWS | Dallas | 245 | Yellowstone County |
| Golden Sunlight Mines Inc | MT0002916 | NTNCWS | Whitehall | 160 | Jefferson County |
| Golden Valley Colony | MT0001580 | CWS | Ryegate | 100 | Golden Valley County |
| Goodan Keil Co Water Dist | MT0002393 | CWS | Missoula | 207 | Missoula County |
| Gore Hill County Water Dist | MT0000232 | CWS | Great Falls | 500 | Cascade County |
| Gosi Enterprises Llc | MT0004490 | NTNCWS | Missoula | 150 | Missoula County |
| Grace Bible Church | MT0004484 | NTNCWS | Bozeman | 1,350 | Gallatin County |
| Grace Lutheran Childcare And Preschool | MT0003860 | NTNCWS | Hamilton | 100 | Ravalli County |
| Grand Valley Estates Subdivision | MT0004474 | CWS | Helena | 50 | Lewis and Clark County |
| Grandview Trailer Court | MT0004686 | CWS | Port Orchard | 165 | Cascade County |
| Granite Park Water Association | MT0004563 | CWS | Billings | 250 | Yellowstone County |
| Granite Water Works | MT0003509 | NTNCWS | Philipsburg | 27 | Granite County |
| Grant Creek Water Users Association Inc | MT0003305 | CWS | Missoula | 380 | Missoula County |
| Grass Land Estates | MT0004448 | CWS | East Helena | 228 | Lewis and Clark County |
| Grass Range Town Of | MT0000231 | CWS | Grass Range | 102 | Fergus County |
| Grass Valley Industrial Park | MT0005200 | NTNCWS | Missoula | 1,400 | Missoula County |
| Grassland Colony | MT0004832 | CWS | Great Falls | 80 | Cascade County |
| Gravel Hollow Llc | MT0004564 | CWS | Gallatin Gateway | 50 | Gallatin County |
| Gray Wolf Casino | 083090301 | NTNCWS | Pablo | 223 | |
| Gray Wolf Village | 083090038 | CWS | Pablo | 32 | Missoula County |
| Graymont Western Us Inc | MT0003705 | NTNCWS | Townsend | 52 | Broadwater County |
| Great Bear Estates | MT0004542 | CWS | Columbia Falls | 32 | Flathead County |
| Great Beginnings Montessori School | MT0004566 | NTNCWS | Bozeman | 61 | Gallatin County |
| Great Falls Koa Kampground | MT0000763 | NTNCWS | Great Falls | 287 | Cascade County |
| Great Falls Rv Park | MT0000027 | CWS | Great Falls | 274 | Cascade County |
| Green Acres Court | MT0000109 | CWS | Kalispell | 85 | Flathead County |
| Green Meadow Country Club | MT0001452 | NTNCWS | Helena | 471 | Lewis and Clark County |
| Green Tree Meadows County W And S Dist | MT0003194 | CWS | Bigfork | 237 | Flathead County |
| Greenacres County Water And Sewer Dist | MT0001923 | CWS | Kalispell | 450 | Flathead County |
| Greenfield Elem School Dist 75 | MT0003015 | NTNCWS | Fairfield | 90 | Teton County |
| Greenfield Mobile Home Park | MT0000373 | CWS | Vancouver | 620 | Missoula County |
| Greenland Mobile Home Park | MT0000372 | CWS | Missoula | 163 | Missoula County |
| Greenwood Trailer Court | MT0000449 | CWS | Missoula | 53 | Missoula County |
| Greenwood Village Rv And Mhp | MT0003602 | CWS | Kalispell | 195 | Flathead County |
| Grinell Estates Hoa | MT0003261 | CWS | Frenchtown | 48 | Missoula County |
| Grizzly Disposal & Recycling | MT0004137 | NTNCWS | Missoula | 37 | Missoula County |
| Grove The | MT0004211 | CWS | Missoula | 50 | Missoula County |
| Gsk Biologicals | MT0004606 | NTNCWS | Hamilton | 315 | Ravalli County |
| H E Robinson Vo Ag Center | MT0004046 | NTNCWS | Kalispell | 260 | Flathead County |
| Hadley Road Hoa | MT0004645 | CWS | Kalispell | 33 | Flathead County |
| Halfmoon Meadows Hoa | MT0004976 | CWS | Kalispell | 25 | Flathead County |
| Halfmoon Mobile Home Park Inc | MT0003531 | CWS | Columbia Falls | 60 | Flathead County |
| Hamilton Christian Academy | MT0001059 | NTNCWS | Missoula | 70 | Ravalli County |
| Hamilton Mobile Village | MT0001079 | CWS | Missoula | 53 | Ravalli County |
| Hangmans Tree Wua | MT0000128 | CWS | Clancy | 158 | Jefferson County |
| Hansons Trailer Court | MT0000095 | CWS | Kalispell | 40 | Flathead County |
| Happy Valley Mhp | MT0000377 | CWS | Missoula | 55 | Missoula County |
| Happy Valley Water Dist B Kspl | MT0001984 | CWS | Columbia Falls | 207 | Flathead County |
| Hardin Subdivision | MT0004263 | CWS | Bozeman | 28 | Big Horn County, Gallatin County |
| Harlem City Of | MT0000239 | CWS | Harlem | 820 | Blaine County |
| Harlowton City Of | MT0000240 | CWS | Harlowton | 1,050 | Wheatland County |
| Harrington Bottling Co | MT0003882 | NTNCWS | Butte | 1,001 | Silver Bow County |
| Harrison School District No 23 | MT0003790 | NTNCWS | Harrison | 100 | Madison County |
| Hartland Colony | MT0004072 | CWS | Havre | 73 | Blaine County |
| Harvest View Hoa | MT0004842 | CWS | Wilmington | 25 | Flathead County |
| Harveys Mobile Home Park | MT0000453 | CWS | Missoula | 98 | Missoula County |
| Hawarden Square Butte Water | MT0003522 | CWS | Geraldine | 50 | Chouteau County |
| Hawthorn Springs Property Owners Assoc | MT0004516 | CWS | Missoula | 165 | Missoula County |
| Hays/White Cow Canyon Ws | 083090044 | CWS | Harlem | 840 | Blaine County |
| Headquarters Apgar | MT0003176 | CWS | West Glacier | 500 | Flathead County |
| Heart Butte School | 083090009 | CWS | Heart Butte | 250 | Pondera County |
| Heart Butte Water System | 083090005 | CWS | Browning | 400 | Pondera County |
| Hearts And Hands Montessori | MT0004715 | NTNCWS | Belgrade | 42 | Gallatin County |
| Hebgen Lake Estates Co Water Sewer Distr | MT0001983 | CWS | West Yellowstone | 230 | Gallatin County |
| Helena Flats School Dist 15 | MT0000927 | NTNCWS | Kalispell | 200 | Flathead County |
| Helena Leisure Llc | MT0000590 | CWS | Helena | 1,200 | Lewis and Clark County |
| Helena North Koa | MT0003679 | CWS | Kalispell | 50 | Lewis and Clark County |
| Helena Rv And Mobile Home Park | MT0000426 | CWS | Hailey | 250 | Lewis and Clark County |
| Heritage Christian School | MT0003518 | NTNCWS | Bozeman | 272 | Gallatin County |
| Heron Community Water System | MT0000247 | CWS | Heron | 84 | Sanders County |
| Hi Heat Industries Inc | MT0004110 | NTNCWS | Lewistown | 75 | Fergus County |
| Hi-Line Colony | MT0005185 | CWS | Chester | 92 | Liberty County |
| Hidden Heights Hoa | MT0002120 | CWS | Missoula | 65 | Missoula County |
| Hidden Lake Colony | MT0003932 | CWS | Cut Bank | 80 | Glacier County |
| Hidden Lake Yellowstone County W And S D | MT0003374 | CWS | Billings | 350 | Yellowstone County |
| Hidden Meadow Management Llc | MT0004735 | NTNCWS | Columbia Falls | 32 | Flathead County |
| Hidden Valley Colony | MT0004987 | CWS | Gildford | 80 | Hill County |
| Hidden Valley Owner Llc | MT0000035 | CWS | San Diego | 200 | Gallatin County |
| Hideaway Tr Pk Columbia Falls | MT0001737 | CWS | Kalispell | 75 | Flathead County |
| High Country Mhp Llc | MT0001850 | CWS | Whitefish | 76 | Mineral County |
| High Plains H2O Llc | MT0005192 | CWS | Great Falls | 25 | Cascade County |
| High Quality H2O | MT0002540 | CWS | Missoula | 200 | Missoula County |
| Highland Park Utilities Assn | MT0000570 | CWS | Glendive | 500 | Dawson County |
| Highwood County Water And Sewer District | MT0000248 | CWS | Highwood | 280 | Chouteau County |
| Highwood Mobile Home Park | MT0004681 | CWS | Great Falls | 400 | Cascade County |
| Hildreth Subdivision No 2 | MT0002486 | CWS | Dillon | 300 | Beaverhead County |
| Hildreth Subdivision No 3 | MT0003968 | CWS | Dillon | 128 | Beaverhead County |
| Hill County Water Districts | MT0000249 | CWS | Hingham | 1,720 | Hill County |
| Hillcrest Colony | MT0004661 | CWS | Power | 89 | Cascade County |
| Hillcrest Community Water | MT0000430 | CWS | Kalispell | 65 | Flathead County |
| Hilldale Colony | MT0001774 | CWS | Havre | 79 | Hill County |
| Hillside Colony Inc | MT0001782 | CWS | Sweet Grass | 100 | Toole County |
| Hillside Homes | MT0000074 | CWS | Bigfork | 35 | Flathead County |
| Hillside Village | MT0003808 | CWS | Dallas | 650 | Yellowstone County |
| Hilltop Colony | MT0004854 | CWS | Stockett | 100 | Cascade County |
| Hilltop Terrace Subdivision | MT0001922 | CWS | Kalispell | 230 | Flathead County |
| Hilltop Water | MT0005205 | CWS | Columbus | 50 | Stillwater County |
| Hinsdale Water Department | MT0000250 | CWS | Hinsdale | 250 | Valley County |
| Hobson Town Of | MT0004382 | CWS | Hobson | 125 | Judith Basin County |
| Hobson School | MT0001410 | NTNCWS | Hobson | 150 | Judith Basin County |
| Holbrook Estates | MT0005154 | CWS | Kalispell | 120 | Flathead County |
| Hollywood Heights Trailer Park Llc | MT0000454 | CWS | Missoula | 220 | Missoula County |
| Holmberg Village Estates | MT0004190 | CWS | Helena | 225 | Lewis and Clark County |
| Home 40 Public Water Supply | MT0004960 | CWS | Bozeman | 45 | Gallatin County |
| Homestead Acres County Water And Sewer | MT0000526 | CWS | Great Falls | 500 | Cascade County |
| Homestead Valley Wua Hvha | MT0003251 | CWS | East Helena | 105 | Lewis and Clark County |
| Honey Lane Community | MT0001080 | CWS | Stevensville | 50 | Ravalli County |
| Horizon Colony | MT0004529 | CWS | Cut Bank | 150 | Glacier County |
| Hot Springs Court | 083090312 | CWS | Seattle | 26 | Sanders County |
| Hot Springs Municipal Water | MT0000251 | CWS | Hot Springs | 982 | Sanders County |
| Houle Villa Water System | 083090026 | CWS | Pablo | 50 | Lake County |
| Hoving Business Center | MT0004896 | NTNCWS | Helena | 170 | Lewis and Clark County |
| Hungry Horse Co Water And Sewer District | MT0000253 | CWS | Hungry Horse | 1,135 | Flathead County |
| Hungry Horse Dam | MT0001790 | NTNCWS | Hungry Horse | 30 | Flathead County |
| Hunters Trailer Ct Anaconda | MT0000649 | CWS | Missoula | 38 | Deer Lodge County |
| Huntley Yellowstone Co Water And Sewer | MT0000254 | CWS | Huntley | 230 | Yellowstone County |
| Hysham Town Of | MT0000428 | CWS | Hysham | 262 | Treasure County |
| I 94 Mobile Home Park | MT0000410 | CWS | Seattle | 90 | Dawson County |
| Indian Springs Ranch Sub | MT0004611 | CWS | Eureka | 455 | Lincoln County |
| Iron Horse Homeowners Assoc | MT0004052 | CWS | Columbia Falls | 335 | Flathead County |
| Island Mountain Development Group | 083090040 | NTNCWS | Hays | 150 | |
| Jefferson Hills Wua | MT0002978 | CWS | Helena | 780 | Jefferson County |
| Jefferson School District No 1 | MT0001209 | NTNCWS | Glendive | 270 | Dawson County |
| Jefferson Tracts Assoc Inc | MT0003614 | CWS | Clancy | 80 | Jefferson County |
| Jens Little Rugrats Daycare Unapproved | MT0005264 | NTNCWS | Belgrade | 50 | Gallatin County |
| Jette Lake Landowners Association | MT0003102 | CWS | Polson | 295 | Lake County |
| Jette Meadows Lake Co W And S Dist | MT0003100 | CWS | Polson | 375 | Lake County |
| Jim Darcy School District No 1 | MT0001451 | NTNCWS | Helena | 575 | Lewis and Clark County |
| Johnsons Mobile Home Park | MT0000529 | CWS | Libby | 35 | Lincoln County |
| Joliet Town Of | MT0000256 | CWS | Joliet | 600 | Carbon County |
| Jordan Town Of | MT0000257 | CWS | Jordan | 364 | Garfield County |
| Judith Gap Town Of | MT0000258 | CWS | Judith Gap | 126 | Wheatland County |
| Juniper Bay Villas | MT0004576 | CWS | Kalispell | 26 | Flathead County |
| Juniper Trailer Court Msla | MT0003527 | CWS | Missoula | 35 | Missoula County |
| Kalispell Industrial Center Wua | MT0004029 | NTNCWS | Kalispell | 55 | Flathead County |
| Kalispell Montessori School | MT0004105 | NTNCWS | Bigfork | 200 | Flathead County |
| Katoonah Lodges | MT0003692 | CWS | Missoula | 258 | Missoula County |
| Keller Subdivision No 2 Hoa | MT0002485 | CWS | Dillon | 300 | Beaverhead County |
| Kenworth Sales Co | MT0003936 | NTNCWS | Spokane | 90 | Missoula County |
| Kenyon Noble Lumber Company | MT0003984 | NTNCWS | Bozeman | 240 | Gallatin County |
| Kettlehouse Brewing And Amphitheater | MT0004903 | NTNCWS | Bonner | 85 | Missoula County |
| Kevin Town Of | MT0000265 | CWS | Kevin | 290 | Toole County |
| Kicking Horse Job Corps | 083090037 | NTNCWS | Pablo | 54 | |
| Kid Corral Day Care | MT0004370 | NTNCWS | Shepherd | 60 | Yellowstone County |
| Kila School District No 20 | MT0000892 | NTNCWS | Kalispell | 160 | Flathead County |
| King Ranch Colony | MT0000432 | CWS | Lewistown | 56 | Fergus County |
| King Ranch Subdivision | MT0004158 | CWS | Frenchtown | 70 | Missoula County |
| Kingsbury Colony | MT0002031 | CWS | Valier | 120 | Pondera County |
| Kinsey School District 63 | MT0001191 | NTNCWS | Miles City | 86 | Custer County |
| Kircher School Dist 03 | MT0003178 | NTNCWS | Miles City | 45 | Custer County |
| Kokanee Bend Hoa | MT0002997 | CWS | Columbia Falls | 230 | Flathead County |
| Kootenai Creek Village | MT0004241 | CWS | Hamilton | 175 | Ravalli County |
| Kootenai Woods Subdivision | MT0004400 | CWS | Bigfork | 53 | Lake County |
| La Casa Grande Water And Sewer District | MT0001924 | CWS | East Helena | 404 | Lewis and Clark County |
| Lake County Transfer Station | MT0004515 | NTNCWS | Ronan | 62 | Lake County |
| Lakeshore Heights Hoa | MT0001743 | CWS | Columbia Falls | 100 | Flathead County |
| Lakeside Water System | MT0000266 | CWS | Lakeside | 1,225 | Flathead County |
| Lakeview Park Estates Homeowners Assoc | MT0000073 | CWS | Lakeside | 92 | Flathead County |
| Lambert Sewer And Water Assn | MT0000269 | CWS | Lambert | 150 | Richland County |
| Lame Deer High School | 083090067 | NTNCWS | Lame Deer | 291 | |
| Lame Deer Water System | 083090064 | CWS | Lame Deer | 2,605 | Big Horn County, Rosebud County |
| Lamotte School District No 43 | MT0001249 | NTNCWS | Bozeman | 72 | Gallatin County |
| Landmark Subdivision | MT0004262 | CWS | Bozeman | 750 | Gallatin County |
| Lavina School District | MT0001386 | NTNCWS | Lavina | 94 | Golden Valley County |
| Lazy J South Subdivision | MT0004432 | CWS | Big Sky | 122 | Gallatin County |
| Ledgewood Estates | MT0004209 | CWS | Bigfork | 35 | Flathead County |
| Lehrkinds Big Spring Water | MT0001229 | NTNCWS | Bozeman | 2,575 | Fergus County |
| Lehrkinds Water Bottling Plant | MT0004546 | NTNCWS | Bozeman | 30 | Gallatin County |
| Lewis And Clark Trailer Court | MT0000370 | CWS | Missoula | 110 | Missoula County |
| Lexley Acres Mobile Home Park | MT0000461 | CWS | Belgrade | 250 | Gallatin County |
| Libby Creek Mobile Park Llc-Unapproved | MT0005241 | CWS | Libby | 35 | Lincoln County |
| Libby Dam Project | MT0002582 | NTNCWS | Libby | 95 | Lincoln County |
| Liberty Lake Properties Llc | MT0005085 | NTNCWS | Missoula | 39 | Missoula County |
| Lil Sprouts Daycare | MT0005144 | NTNCWS | Florence | 43 | Ravalli County |
| Lima Town Of | MT0000276 | CWS | Lima | 279 | Beaverhead County |
| Lincoln Ranger Station | MT0062323 | NTNCWS | Lincoln | 155 | Lewis and Clark County |
| Lincoln School District No 38 | MT0001468 | NTNCWS | Lincoln | 300 | Lewis and Clark County |
| Lion Mountain Homeowners Assoc | MT0000392 | CWS | Columbia Falls | 204 | Flathead County |
| Lithia Ford Of Missoula | MT0004478 | NTNCWS | Missoula | 87 | Missoula County |
| Little Bighorn Battlefield Nm | MT0000191 | NTNCWS | Crow Agency | 2,020 | Big Horn County |
| Lodge Grass Town Of | MT0000277 | CWS | Lodge Grass | 480 | Big Horn County |
| Loenbro Fabrication Facility | MT0004898 | NTNCWS | Black Eagle | 30 | Cascade County |
| Loenbro Office Building | MT0004897 | NTNCWS | Black Eagle | 45 | Cascade County |
| Lolo Water And Sewer Dist | MT0000278 | CWS | Lolo | 3,315 | Missoula County |
| Loma County Water District | MT0002669 | CWS | Loma | 200 | Chouteau County |
| Lone Mountain Guest Ranch | MT0001820 | NTNCWS | Big Sky | 75 | Gallatin County |
| Lone Rock School District No 13 | MT0001085 | NTNCWS | Stevensville | 280 | Ravalli County |
| Lone View Ridge Water System | MT0004470 | CWS | Big Sky | 37 | Madison County |
| Loring Hutterian Brethren Inc | MT0003524 | CWS | Loring | 45 | Phillips County |
| Loves Travel Stop & Country Store Wye | MT0005001 | NTNCWS | Oklahoma City | 1,050 | Missoula County |
| Lower Pioneer Mountain Water System | MT0004462 | CWS | Big Sky | 350 | Madison County |
| M&S Meats | MT0005248 | NTNCWS | Kalispell | 49 | Flathead County |
| Magnolia Estates | MT0004021 | CWS | Missoula | 140 | Missoula County |
| Magris Talc Usa Inc Sappington Mill | MT0003504 | NTNCWS | Three Forks | 55 | Gallatin County |
| Magris Talc Usa Inc Yellowstone Mine | MT0003824 | NTNCWS | Three Forks | 32 | Madison County |
| Malta City Of | MT0000284 | CWS | Malta | 1,800 | Phillips County |
| Manhattan Town Of | MT0000285 | CWS | Manhattan | 1,800 | Gallatin County |
| Manhattan Camper Court | MT0001821 | CWS | Manhattan | 105 | Gallatin County |
| Manhattan Christian Schools | MT0001279 | NTNCWS | Manhattan | 400 | Gallatin County |
| Marion School District 54 | MT0000936 | NTNCWS | Kalispell | 135 | Flathead County |
| Marketing Concepts Inc | MT0003330 | NTNCWS | Glendive | 85 | Dawson County |
| Martin City County Water District | MT0000286 | CWS | Martin City | 340 | Flathead County |
| Martinsdale Colony | MT0000445 | CWS | Martinsdale | 150 | Meagher County, Wheatland County |
| Martinsdale Water And Sewer District | MT0000287 | CWS | Martinsdale | 75 | Meagher County |
| Masonic Home Of Montana | MT0000245 | CWS | East Helena | 90 | Lewis and Clark County |
| Mccann'S Water Service Llc | MT0004705 | CWS | Shepherd | 25 | Yellowstone County |
| Mcdonald Trailer Ct | MT0000402 | CWS | East Helena | 75 | Lewis and Clark County |
| Mcgowan Water Cond Inc | MT0004254 | NTNCWS | Missoula | 1,207 | Missoula County |
| Mcgrade Center | MT0001148 | NTNCWS | Libby | 50 | Lincoln County |
| Mchugh Mobile Home Park | MT0002917 | CWS | Vancouver | 490 | Lewis and Clark County |
| Meadow Brook Park | MT0004530 | CWS | Missoula | 120 | Missoula County |
| Meadow Hills Water And Sewer District | MT0002925 | CWS | Columbia Falls | 130 | Flathead County |
| Meadow Lake Co Water And Sewer District | MT0000914 | CWS | Columbia Falls | 950 | Flathead County |
| Meadow Manor | MT0004397 | CWS | Kalispell | 410 | Flathead County |
| Meadowland Hoa | MT0001670 | CWS | Columbia Falls | 150 | Flathead County |
| Meadowlark Mobile Home Park | MT0000082 | CWS | Buena Park | 55 | Flathead County |
| Medicine Lake Town Of | MT0000289 | CWS | Medicine Lake | 600 | Sheridan County |
| Melstone Town Of | MT0000290 | CWS | Melstone | 170 | Musselshell County |
| Middle Creek Montessori School | MT0004567 | NTNCWS | Bozeman | 140 | Gallatin County |
| Midway Colony Inc | MT0004628 | CWS | Conrad | 92 | Pondera County |
| Midway Townhomes Wua | MT0005065 | CWS | Billings | 75 | Yellowstone County |
| Milford Colony Inc | MT0001646 | CWS | Wolf Creek | 67 | Lewis and Clark County |
| Miller Colony | MT0001649 | CWS | Choteau | 84 | Teton County |
| Milltown Water Users Asso North | MT0002464 | CWS | Milltown | 43 | Missoula County |
| Milltown Water Users Asso South | MT0003088 | CWS | Missoula | 85 | Missoula County |
| Mission Dam Water System | 083090029 | CWS | Pablo | 87 | Lake County |
| Mission Meadows Rv Campsite Park, Inc | MT0000621 | CWS | Missoula | 200 | Lake County |
| Mission Mountain Lake Co W And S Dist | MT0003801 | CWS | Ronan | 118 | Lake County |
| Mission Mountain View Hoa | MT0003157 | CWS | Ronan | 80 | Lake County |
| Missoula Co High School Vo Ag | MT0003505 | NTNCWS | Missoula | 105 | Missoula County |
| Missoula Country Club | MT0002490 | NTNCWS | Missoula | 240 | Missoula County |
| Missoula County Public Water Dept | MT0004479 | NTNCWS | Missoula | 38 | Missoula County |
| Missoula Koa & El Mar Tlr Village | MT0002517 | CWS | Bend | 499 | Missoula County |
| Missoula Village West Tr Ct | MT0003012 | CWS | Missoula | 68 | Missoula County |
| Missouri Meadows Community Inc | MT0000053 | CWS | Highlands Ranch | 85 | Cascade County |
| Mitchell Court Apartments | MT0005190 | CWS | Billings | 80 | Yellowstone County |
| Mnihnapa Water System | 083090047 | CWS | Harlem | 220 | Blaine County |
| Mobile City 3 | MT0005088 | CWS | Billings | 40 | Lewis and Clark County |
| Mobile City Home Park No 1 | MT0000601 | CWS | Billings | 100 | Lewis and Clark County |
| Mobile City Home Park No 2 | MT0003043 | CWS | Billings | 300 | Lewis and Clark County |
| Mobile City Trailer Court | MT0000646 | CWS | Missoula | 175 | Missoula County |
| Montana Artesian Water Flathead Co | MT0004981 | NTNCWS | Kalispell | 25 | Flathead County |
| Montana Aviation Research Co | MT0000416 | NTNCWS | Glasgow | 70 | Valley County |
| Montana Christian College | MT0004270 | CWS | Libby | 105 | Flathead County |
| Montana City School Dist 27 | MT0001393 | NTNCWS | Clancy | 534 | Jefferson County |
| Montana Knife Company | MT0005199 | NTNCWS | Frenchtown | 253 | Missoula County |
| Montana Precision Products | MT0004763 | NTNCWS | Butte | 260 | Silver Bow County |
| Montana Resources Llc | MT0005224 | NTNCWS | Butte | 500 | Silver Bow County |
| Montana State Hospital Complex | MT0004805 | CWS | Warm Springs | 721 | Deer Lodge County |
| Montana State Prison | MT0000198 | CWS | Deer Lodge | 2,100 | Granite County, Powell County |
| Montana Technological University | MT0004823 | NTNCWS | Butte | 3,200 | Silver Bow County |
| Montana Trailer Court | MT0003215 | CWS | Missoula | 73 | Missoula County |
| Montessori Island School | MT0004578 | NTNCWS | Livingston | 64 | Park County |
| Moonlight Estates Hoa | MT0004872 | CWS | Helena | 44 | Lewis and Clark County |
| Moore Town Of | MT0000295 | CWS | Moore | 186 | Fergus County |
| Morin Elementary School | MT0002048 | NTNCWS | Billings | 48 | Yellowstone County |
| Morning Star | MT0001672 | CWS | Bigfork | 85 | Flathead County |
| Mount Pleasant Estates | MT0000644 | CWS | Sidney | 45 | Richland County |
| Mountain Acres Mb Hm Pk | MT0003809 | CWS | Lincoln | 320 | Fergus County |
| Mountain Heritage Water System | MT0002873 | CWS | Helena | 175 | Lewis and Clark County |
| Mountain Meadow Herbs | MT0004853 | NTNCWS | Kalispell | 45 | Flathead County |
| Mountain Meadows Estates Llp | MT0001791 | CWS | San Diego | 300 | Gallatin County |
| Mountain Shadows Estates Stevensville | MT0002132 | CWS | Missoula | 55 | Ravalli County |
| Mountain States Leasing Butte Llc | MT0003890 | NTNCWS | Butte | 170 | Silver Bow County |
| Mountain View Colony | MT0004058 | CWS | Broadview | 114 | Yellowstone County |
| Mountain View Mb Hm Pk | MT0001921 | CWS | Melville | 150 | Broadwater County |
| Mountain View Timbers Hoa | MT0004874 | CWS | Bigfork | 36 | Flathead County |
| Mountain View Trailer Court | MT0000455 | CWS | Missoula | 42 | Missoula County |
| Mountain Villa Apts Kalispell | MT0002640 | CWS | Coeur D'Alene | 300 | Flathead County |
| Msu Northern | MT0004812 | NTNCWS | Havre | 1,937 | Hill County |
| Mt Air Natl Guard 120Th Air Lift Wing | MT0004789 | NTNCWS | Great Fallls | 350 | Cascade County |
| Mt Ellis Academy | MT0001262 | CWS | Bozeman | 106 | Gallatin County |
| Mt Moonlight Basin | MT0004023 | CWS | Belgrade | 355 | Madison County |
| Murdochs Ranch Supply Bozeman | MT0004838 | NTNCWS | Bozeman | 280 | Gallatin County |
| Musselshell Community County Wsd | MT0000296 | CWS | Musselshell | 75 | Musselshell County |
| Mvp Holding Llc | MT0003749 | NTNCWS | Missoula | 74 | Missoula County |
| Mystic Heights Hoa Bozeman | MT0000795 | CWS | Bozeman | 96 | Gallatin County |
| Nashua Town Of | MT0000297 | CWS | Nashua | 300 | Valley County |
| Ncmrwa Pondera Co Service Area | MT0004834 | CWS | Helena | 144 | Lewis and Clark County, Pondera County |
| Ncmrwa North Havre Cwd Leg | MT0004720 | CWS | Helena | 90 | Hill County |
| Ncmrwa Shelby To Ethridge | MT0004936 | CWS | Helena | 70 | Toole County |
| Ncmrwa Etheridge To Cutbank | MT0004993 | CWS | Helena | 25 | Glacier County |
| Ncmrwa North Shelby | MT0005064 | CWS | Helena | 300 | Toole County |
| Ncmrwa Tiber Service Area | MT0004719 | CWS | Helena | 200 | Liberty County |
| Neihart Town Of | MT0000298 | CWS | Neihart | 229 | Cascade County |
| New Castle Court | MT0004322 | CWS | Missoula | 55 | Missoula County |
| New Miami Colony | MT0001914 | CWS | Conrad | 130 | Pondera County |
| New Rockport Colony Inc | MT0001776 | CWS | Choteau | 160 | Teton County |
| Nine Mile Co Water And Sewer District | MT0005075 | CWS | Sunburst | 90 | Toole County |
| Nine Mile Ranger Station And Pa | MT0062578 | NTNCWS | Huson | 70 | Missoula County |
| North Baker Water And Or Sewer Dist | MT0004404 | CWS | Baker | 112 | Fallon County |
| North Davis Duplexes 421 | MT0002121 | CWS | Missoula | 33 | Missoula County |
| North Forestvale Homeowners | MT0001793 | CWS | Helena | 98 | Lewis and Clark County |
| North Geraldine Water System | MT0003521 | CWS | Geraldine | 50 | Chouteau County |
| North Harlem Colony | MT0001771 | CWS | Harlem | 42 | Blaine County |
| North Haven Heights Water Assoc Inc | MT0000087 | CWS | Kalispell | 95 | Flathead County |
| North Havre County Water Dist | MT0002988 | CWS | Havre | 90 | Hill County |
| North Shore Estates Hoa | MT0003556 | CWS | Thompson Falls | 65 | Sanders County |
| North Star Zoot Water | MT0004284 | CWS | Bozeman | 4,323 | Gallatin County |
| North Star Pud | MT0004264 | CWS | Helena | 715 | Lewis and Clark County |
| North Valley County Water And Sewer Dist | MT0003595 | CWS | Glasgow | 450 | Valley County |
| Northern Cheyenne Youth Service Center | 083090066 | NTNCWS | Lame Deer | 25 | |
| Northern Pines Community Hoa | MT0004193 | CWS | Columbia Falls | 295 | Flathead County |
| Northfork Tr Ct Columbia Falls | MT0000110 | CWS | Garden City | 48 | Flathead County |
| Northwest Indian Bible School | MT0003958 | CWS | Alberton | 118 | Missoula County |
| Northwest Water Conditioning Culligan W | MT0003473 | NTNCWS | Laurel | 300 | Yellowstone County |
| Northwest Water Treatment Co | MT0003413 | NTNCWS | Bozeman | 118 | Gallatin County |
| Northwoods Water System Coop Inc | MT0001736 | CWS | Columbia Falls | 135 | Flathead County |
| Noxon Water District | MT0000299 | CWS | Noxon | 330 | Sanders County |
| Oak Ridge Estates | MT0004250 | CWS | Billings | 200 | Yellowstone County |
| Oilmont County Water District | MT0000587 | CWS | Sunburst | 300 | Toole County |
| Old Hays | 083090045 | CWS | Harlem | 80 | Blaine County |
| Old Hellgate Village Msla | MT0002635 | CWS | Missoula | 140 | Missoula County |
| Old Mill Peninsula Hoa | MT0004192 | CWS | Missoula | 40 | Mineral County |
| Opheim Town Of | MT0000301 | CWS | Opheim | 111 | Valley County |
| Outback Mobile Home Settlement | MT0000062 | CWS | Whitefish | 80 | Flathead County |
| Outlook County Sewer And Water | MT0003312 | CWS | Outlook | 96 | Sheridan County |
| Overlook Subdivision | MT0003792 | CWS | Polson | 49 | Lake County |
| Pablo Lake County Water And Sewer Dist | MT0001917 | CWS | Pablo | 2,175 | Lake County |
| Pache Water System | 083090036 | CWS | Pablo | 276 | Lake County |
| Pacific Steel And Recycling | MT0004849 | NTNCWS | Great Falls | 60 | Yellowstone County |
| Palisades Apartments | MT0000145 | CWS | Miles City | 50 | Custer County |
| Panoramic Mountain River Heights W Dist | MT0000089 | CWS | Kalispell | 65 | Flathead County |
| Paradise Pines | MT0001018 | CWS | Polson | 95 | Lake County |
| Paradise Water District | MT0000385 | CWS | Paradise | 200 | Sanders County |
| Park City School K 12 | MT0002026 | NTNCWS | Park City | 300 | Stillwater County |
| Park Evergreen Trailer Court | MT0000421 | CWS | Corpus Christi | 87 | Lewis and Clark County |
| Park Garden Estates | MT0000050 | CWS | Great Falls | 50 | Cascade County |
| Paws Up Angus Ranch Main Complex | MT0004454 | NTNCWS | Greenough | 327 | Missoula County |
| Peak Health And Wellness Center | MT0004589 | NTNCWS | Missoula | 506 | Missoula County |
| Pebble Gardens Mobile Home Ct | MT0000603 | CWS | East Helena | 125 | Lewis and Clark County |
| Peks Mobile Home Court | MT0004714 | CWS | Billings | 95 | Yellowstone County |
| Pele Park | MT0000593 | CWS | East Helena | 186 | Lewis and Clark County |
| Perrys Water Service | MT0004869 | CWS | Chinook | 100 | Blaine County |
| Peters - Priske Apartments Missoula | MT0004933 | CWS | Missoula | 33 | Missoula County |
| Pettyjohns The Water Store | MT0003370 | NTNCWS | Kalispell | 225 | Flathead County |
| Pheasant Haven Estates | MT0004545 | CWS | Kalispell | 53 | Flathead County |
| Philipsburg Town Of | MT0000304 | CWS | Philipsburg | 1,360 | Granite County |
| Phillips County Zortman Water And Sewer | MT0001623 | CWS | Zortman | 169 | Phillips County |
| Phoenix Park | MT0000594 | CWS | East Helena | 36 | Lewis and Clark County |
| Piegan Border Station | MT0003334 | CWS | Helena | 94 | Glacier County |
| Pine Creek School District 19 | MT0001595 | NTNCWS | Livingston | 50 | Park County |
| Pine Crest Tr Pk | MT0000497 | CWS | Campbell | 54 | Park County |
| Pine Hills Youth Correct Facil | MT0000292 | CWS | Miles City | 193 | Custer County |
| Pinewood Shores Wua | MT0003224 | CWS | Polson | 46 | Lake County |
| Pinewood Village | MT0000275 | CWS | Libby | 160 | Lincoln County |
| Pinnacle Estates Of Glendive | MT0002939 | CWS | Glendive | 50 | Dawson County, Gallatin County |
| Pioneer Business Park Llc | MT0004323 | NTNCWS | Kalispell | 30 | Flathead County |
| Pioneer School Dist 41 | MT0001735 | NTNCWS | Billings | 70 | Yellowstone County |
| Pioneer Water Service | MT0004226 | CWS | Billings | 900 | Yellowstone County |
| Pipkin Commercial Subdivision | MT0004313 | NTNCWS | Belgrade | 50 | Gallatin County |
| Plains Town Of | MT0000305 | CWS | Plains | 1,700 | Sanders County |
| Pleasant Grove Manufactured Home Sites | MT0005211 | CWS | Kalispell | 70 | Flathead County |
| Pleasant Hill Estates Hoa | MT0000088 | CWS | Kalispell | 90 | Flathead County |
| Pleasant Park Community Inc | MT0000028 | CWS | Great Falls | 125 | Cascade County |
| Pleasant Valley Colony | MT0003304 | CWS | Belt | 120 | Cascade County |
| Pleasant View Homesites W And S District | MT0000086 | CWS | Kalispell | 85 | Flathead County |
| Pleasant View Water And Sewer District | MT0004671 | CWS | Polson | 45 | Lake County |
| Plentywood Water Department | MT0000306 | CWS | Plentywood | 1,700 | Sheridan County |
| Plevna Town Of | MT0000307 | CWS | Plevna | 130 | Fallon County |
| Pondera Colony Water Systems | MT0003744 | CWS | Valier | 112 | Pondera County |
| Ponderilla Hills Lake County Water Sewer | MT0003103 | CWS | Polson | 35 | Lake County |
| Ponderosa Homeowners Assn Inc | MT0002863 | CWS | Kalispell | 246 | Flathead County |
| Ponderosa Mb Home Subd | MT0000548 | CWS | Bozeman | 70 | Gallatin County |
| Ponderosa Mobile Home Park | MT0002131 | CWS | Hamilton | 60 | Ravalli County |
| Poplar, City Of | 083090051 | CWS | Poplar | 3,025 | Roosevelt County |
| Posts Trailer Court | MT0000554 | CWS | Libby | 45 | Lincoln County |
| Potomac Greenough Community Center | MT0003615 | NTNCWS | Bonner | 150 | Missoula County |
| Potomac School Dist 11 | MT0000855 | NTNCWS | Bonner | 160 | Missoula County |
| Potts Trailer Court Belgrade | MT0000033 | CWS | Bozeman | 50 | Gallatin County |
| Power Teton County Water Dist | MT0000311 | CWS | Power | 205 | Teton County |
| Prairie Community Hospital | MT0001543 | NTNCWS | Terry | 80 | Prairie County |
| Prairie Falcon Acres | MT0004483 | CWS | Columbia Falls | 41 | Flathead County |
| Prairie Mobile Village | MT0000600 | CWS | Helena | 163 | Lewis and Clark County |
| Prairie Water Company | MT0003539 | CWS | Great Falls | 1,000 | Cascade County |
| Precision Water | MT0004497 | CWS | Billings | 250 | Yellowstone County |
| Pretty Eagle School | 083090016 | NTNCWS | Ashland | 188 | |
| Proof Research | MT0004819 | NTNCWS | Columbia Falls | 40 | Flathead County |
| Pryor Creek Water Assn | MT0002956 | CWS | Huntley | 475 | Yellowstone County |
| Pryor Water System | 083090012 | CWS | Crow Agency | 406 | Big Horn County |
| Ptarmigan Village Inc | MT0000133 | CWS | Whitefish | 600 | Flathead County |
| Quail Ridge | MT0004283 | CWS | Kalispell | 148 | Flathead County |
| Quality Inn | MT0003834 | NTNCWS | Belgrade | 282 | Gallatin County |
| Quinns Hot Springs Resort | MT0001102 | NTNCWS | Paradise | 155 | Sanders County |
| R J Northern Park | MT0000085 | CWS | Kalispell | 50 | Flathead County |
| Rae Water And Sewer Dist 313 | MT0000628 | CWS | Bozeman | 2,325 | Gallatin County |
| Rainbow Estates | MT0004873 | CWS | Bismarck | 30 | Dawson County |
| Ramsay School District | MT0003436 | NTNCWS | Ramsay | 140 | Silver Bow County |
| Ramsay Water And Sewer District | MT0000578 | CWS | Ramsay | 97 | Silver Bow County |
| Ramshorn View Estates | MT0004035 | CWS | Townsend | 185 | Gallatin County |
| Ranch At Dome Mountain Lodge | MT0005194 | NTNCWS | Emigrant | 125 | Park County |
| Ranch Co Water & Sewer Dist The | MT0003076 | CWS | Bigfork | 90 | Flathead County |
| Ranch Headquarters | MT0003199 | CWS | Gardiner | 85 | Park County |
| Ranchview Estates Wua | MT0003782 | CWS | Helena | 250 | Lewis and Clark County |
| Rapelje Water District | MT0000313 | CWS | Rapelje | 70 | Stillwater County |
| Rau School District No 21 | MT0003089 | NTNCWS | Sidney | 80 | Richland County |
| Ravalli Electric Co Op | MT0005034 | NTNCWS | Missoula | 75 | Ravalli County |
| Rec Advanced Silicon Materials Llc | MT0004040 | NTNCWS | Silver Bow | 210 | Silver Bow County |
| Red Cliff Estates Hoa | MT0004268 | CWS | Clancy | 48 | Jefferson County |
| Red Lodge Water Dept | MT0000314 | CWS | Red Lodge | 2,000 | Carbon County |
| Red Rocks Water System | 084690032 | CWS | Pine Ridge | 125 | Beaverhead County |
| Red Sky Mobile Home Community | MT0004825 | CWS | Dillon | 80 | Cascade County |
| Reed Point High School And Gym | MT0003481 | NTNCWS | Reed Point | 46 | Stillwater County |
| Renae Court Subdivision | MT0004245 | CWS | Missoula | 36 | Missoula County |
| Rexford Town Of | MT0000315 | CWS | Rexford | 160 | Lincoln County |
| Riceville Heights Subdivision | MT0004238 | CWS | Belt | 25 | Cascade County |
| Richey Town Of | MT0000316 | CWS | Richey | 180 | Dawson County |
| Richland Co Valley View Wua | MT0000514 | CWS | Sidney | 85 | Richland County |
| Riders Trailer Court | MT0001376 | CWS | Manhattan | 100 | Gallatin County |
| Ridgeview Subdivision Phase One | MT0005232 | CWS | Logan | 60 | Yellowstone County |
| Ridgeview Water Users Assoc | MT0001934 | CWS | Kalispell | 35 | Flathead County |
| Ridgewood Estates | MT0003175 | CWS | Big Fork | 250 | Lake County |
| Ridgewood Terrace Mhp | MT0004186 | CWS | Lincoln | 280 | Flathead County |
| Rimrock Colony | MT0001783 | CWS | Sunburst | 124 | Toole County |
| Rio Vista Estates Hoa Assoc Inc | MT0004480 | CWS | Laurel | 50 | Carbon County |
| River Acres Inc | MT0000369 | CWS | Missoula | 78 | Missoula County |
| River Bluff Hoa Whitefish | MT0003652 | CWS | Bigfork | 32 | Flathead County |
| River Grove Estates Tr Ct | MT0000123 | CWS | Port Orchard | 100 | Yellowstone County |
| Rivers Edge Mobile Home Park Grt Fls | MT0004687 | CWS | Helena | 75 | Cascade County |
| Rivers Edge Mobile Park Libby | MT0000553 | CWS | Libby | 60 | Lincoln County |
| Rivershore Community Llc | MT0000414 | CWS | Port Orchard | 90 | Cascade County |
| Riverside Mobile Home Park | MT0000108 | CWS | Columbia Falls | 100 | Flathead County |
| Riverside Water And Sewer Dist | MT0002173 | CWS | Bozeman | 344 | Gallatin County |
| Riverview Colony | MT0001777 | CWS | Chester | 130 | Liberty County |
| Riverview Overlook Hoa | MT0004631 | CWS | Kalispell | 33 | Flathead County |
| Riverwalk And Dinos Estates | MT0004506 | CWS | Missoula | 115 | Missoula County |
| Roberts Wua Carbon Co Water And Sewer | MT0000317 | CWS | Roberts | 300 | Carbon County |
| Robinson Water # 1 East | MT0004967 | NTNCWS | Kalispell | 25 | Flathead County |
| Rocking J Ranch | MT0004652 | NTNCWS | Philipsburg | 130 | Granite County |
| Rocking J Ranch Employee Housing | MT0004787 | NTNCWS | Philipsburg | 39 | Granite County |
| Rockport Colony | MT0001778 | CWS | Pendroy | 92 | Teton County |
| Rocky Boy Agency Water System | 083090079 | CWS | Box Elder | 1,442 | Chouteau County, Hill County |
| Rocky Boy'S Rural Water | 083090075 | CWS | Box Elder | 2,000 | Chouteau County, Hill County |
| Rocky Cliff Estates | MT0004459 | CWS | Kalispell | 140 | Flathead County |
| Rocky Creek Tr Court | MT0000115 | CWS | Bozeman | 35 | Gallatin County |
| Rocky Mountain Building Company | MT0003460 | NTNCWS | Hamilton | 75 | Ravalli County |
| Rocky Mountain Hi Rv Park | MT0002812 | CWS | Kalispell | 275 | Flathead County |
| Rocky Mountain Twist | MT0004060 | NTNCWS | Ronan | 195 | Lake County |
| Rocky Mountain Wua | MT0000058 | CWS | Clancy | 30 | Jefferson County |
| Ronan City Of | MT0000318 | CWS | Ronan | 2,483 | Lake County |
| Rosebud School District No 12 | MT0001656 | NTNCWS | Rosebud | 100 | Rosebud County |
| Rosemarys Addition | MT0002743 | CWS | Helena | 30 | Lewis and Clark County |
| Rosewood Acres | MT0004658 | CWS | Kalispell | 50 | Flathead County |
| Rossiter School District 01 | MT0001447 | NTNCWS | Helena | 550 | Lewis and Clark County |
| Round Butte Water Company | MT0000320 | CWS | Ronan | 400 | Lake County |
| Roundup Water Department | MT0000321 | CWS | Roundup | 1,900 | Musselshell County |
| Roy Water And Sewer District | MT0002395 | CWS | Roy | 110 | Fergus County |
| Ruger Water District | MT0004143 | CWS | East Helena | 79 | Lewis and Clark County |
| Ryan Dam Water System | MT0000046 | CWS | Helena | 230 | Cascade County, Lewis and Clark County |
| Ryans Lot | MT0004368 | CWS | Hermosa Beach | 34 | Missoula County |
| Ryegate Town Of | MT0000322 | CWS | Ryegate | 270 | Golden Valley County |
| S&K Electronics | 083090028 | NTNCWS | Pablo | 80 | |
| S&K Housing Authority | 083090317 | NTNCWS | Pablo | 85 | |
| Saco Town Of | MT0000323 | CWS | Saco | 180 | Phillips County |
| Saddle Mountain Corp Clancy | MT0000057 | CWS | Clancy | 350 | Jefferson County |
| Saddleback Ridge Estates | MT0004408 | CWS | Laurel | 150 | Yellowstone County |
| Sage Creek Co Water District | MT0003150 | CWS | Chester | 225 | Hill County, Liberty County |
| Sage Creek Colony | MT0001779 | CWS | Chester | 130 | Liberty County |
| Salish Shores Trade Winds Comm Village | MT0003911 | CWS | Thompson Falls | 215 | Sanders County |
| Sand Coulee Water Users District | MT0000325 | CWS | Sand Coulee | 180 | Cascade County |
| Sanders County Harvest Foods | MT0003709 | NTNCWS | Polson | 445 | Sanders County |
| Sartorie Legacy Homes | MT0005129 | CWS | Billings | 35 | Yellowstone County |
| Savage Public School | MT0001542 | NTNCWS | Savage | 114 | Richland County |
| Sawtooth Villa | MT0003284 | CWS | Cascade | 70 | Ravalli County |
| Schley Water System | 083090030 | CWS | Pablo | 85 | Missoula County |
| Scobey City Of | MT0000326 | CWS | Scobey | 1,026 | Daniels County |
| Seeley Lake Water District | MT0000327 | CWS | Seeley Lake | 1,575 | Missoula County |
| Settlement The | MT0004363 | CWS | Manhattan | 100 | Gallatin County |
| Seville Colony | MT0002974 | CWS | Cut Bank | 116 | Glacier County |
| Seville Water System | 083090008 | CWS | Browning | 300 | Glacier County |
| Shade Tree Mobile Park | MT0004685 | CWS | Helena | 100 | Cascade County |
| Shelby Addition Water District | MT0002800 | CWS | Missoula | 145 | Missoula County |
| Shelter Bay Estates | MT0003376 | CWS | Rollins | 56 | Lake County |
| Shepherd Schools | MT0004289 | NTNCWS | Shepherd | 800 | Yellowstone County |
| Shepherd Water Station | MT0004920 | CWS | Miles City | 100 | Yellowstone County |
| Sheridan Town Of | MT0000329 | CWS | Sheridan | 632 | Madison County |
| Sherwood Water Station | MT0004059 | CWS | Columbus | 25 | Stillwater County |
| Shiloh Road Development | MT0005178 | CWS | Billings | 315 | Yellowstone County |
| Shyrock Motorcoach Community | MT0004944 | CWS | Superior | 150 | Mineral County |
| Signal Peak Energy Bull Mountain Coal | MT0004676 | NTNCWS | Roundup | 250 | Musselshell County |
| Silver Creek Condominiums In Yellowstone | MT0005222 | CWS | Billings | 28 | Yellowstone County |
| Silver Run School | MT0005122 | NTNCWS | Roberts | 50 | Carbon County |
| Simms High School | MT0000715 | NTNCWS | Simms | 180 | Cascade County |
| Sky Ranch Water Association | MT0004198 | CWS | Kalispell | 45 | Flathead County |
| Sky View Estates | MT0004743 | CWS | Kalispell | 60 | Flathead County |
| Skycrest Estates Subdivision | MT0004964 | CWS | Billings | 235 | Yellowstone County |
| Skyline Tr Ct And Rv Park | MT0002515 | CWS | Dillon | 75 | Beaverhead County |
| Skyview Park | MT0002516 | CWS | Kalispell | 55 | Flathead County |
| Skyview Water And Sewer Utility | MT0004039 | CWS | East Helena | 400 | Lewis and Clark County |
| Sleeping Giant Community Inc | MT0000038 | CWS | Livingston | 50 | Park County |
| Smith Mchugh #2 Blr | MT0005253 | CWS | Helena | 68 | Lewis and Clark County |
| Smith Valley School Lower | MT0000935 | NTNCWS | Kalispell | 280 | Flathead County |
| Solid Rock Ventures Llc | MT0004817 | NTNCWS | Kalispell | 90 | Flathead County |
| Somers Co Water And Sewer Dist | MT0000332 | CWS | Somers | 765 | Flathead County |
| Sonju Industrial Inc | MT0004251 | NTNCWS | Bigfork | 70 | Flathead County |
| Sorrel Springs Hoa | MT0000518 | CWS | Frenchtown | 250 | Missoula County |
| Source Giant Springs Inc | MT0003704 | NTNCWS | Great Falls | 3,007 | Cascade County |
| South Chester Water Dist | MT0000007 | CWS | Chester | 55 | Liberty County |
| South Chouteau County Water Dist | MT0001925 | CWS | Highwood | 80 | Chouteau County |
| South Eighty Water | MT0004276 | CWS | Lakeside | 63 | Flathead County |
| South Forestvale Hoa | MT0003881 | CWS | Helena | 82 | Lewis and Clark County |
| South Hills Water Users Association | MT0003104 | CWS | Polson | 60 | Lake County |
| South Wind Water And Sewer District | MT0000025 | CWS | Great Falls | 200 | Cascade County |
| Southern Cross Pud | MT0005157 | CWS | Anaconda | 25 | Deer Lodge County |
| Southside Public Water Supply | MT0002652 | CWS | Kalispell | 306 | Flathead County |
| Spanish Peaks Mountain Club | MT0004588 | CWS | Big Sky | 40 | Gallatin County, Madison County |
| Sphinx Mountain Mb Hm Pk | MT0003755 | CWS | Gardiner | 52 | Park County |
| Spirit Hills Subdivision | MT0004208 | CWS | Bozeman | 230 | Gallatin County |
| Spring Creek Coal Domestic | MT0003952 | NTNCWS | Decker | 200 | Big Horn County |
| Spring Creek Colony Lewistown | MT0000433 | CWS | Lewistown | 48 | Fergus County |
| Spring Creek Mhp | MT0004625 | CWS | St George | 82 | Flathead County |
| Spring Creek Mine | MT0002009 | NTNCWS | Decker | 200 | Big Horn County |
| Spring Meadows County Water District | MT0003630 | CWS | Missoula | 162 | Missoula County |
| Spring Tree Ridge | MT0004419 | CWS | Great Falls | 80 | Cascade County |
| Springdale Hutterite Colony | MT0000134 | CWS | White Sulphur Springs | 87 | Meagher County |
| Springhill Park Subdivision | MT0000796 | CWS | Bozeman | 90 | Gallatin County |
| Springvale Subdivision | MT0001823 | CWS | Belgrade | 150 | Gallatin County |
| Springwater Colony | MT0000719 | CWS | Harlowton | 100 | Wheatland County |
| Spruce Meadows Hoa | MT0004662 | CWS | Kalispell | 40 | Flathead County |
| Spruce Park Mobile Village | MT0000079 | CWS | Billings | 48 | Flathead County |
| St Charles School | MT0003131 | NTNCWS | Ashland | 152 | Big Horn County |
| St Ignatius Town Of | MT0001740 | CWS | St Ignatius | 700 | Lake County, Sanders County |
| St Ignatius (Mission) So.Side | 083090031 | CWS | Pablo | 356 | Lake County |
| St Labre Indian School | MT0000018 | CWS | Ashland | 650 | Rosebud County |
| St Mary Headquarters And Cg | MT0002729 | CWS | West Glacier | 1,030 | Glacier County |
| St Regis School Old Bldg | MT0002488 | NTNCWS | St Regis | 176 | Mineral County |
| Stacey'S Bar-The Westerner | MT0001287 | NTNCWS | Gallatin Gateway | 315 | Gallatin County |
| Stanford Town Of | MT0000334 | CWS | Stanford | 425 | Judith Basin County |
| Stans Garden | MT0004899 | CWS | Belgrade | 100 | Gallatin County |
| Star Mobile Home Park | MT0000034 | CWS | Bozeman | 190 | Gallatin County |
| Starr School Water System | 083090007 | CWS | Browning | 250 | Glacier County |
| Steer Inn Teasers Restaurant And Lounge | MT0002564 | NTNCWS | Three Forks | 233 | Broadwater County |
| Stevensville Town Of | MT0000335 | CWS | Stevensville | 2,090 | Ravalli County |
| Still River Estates Subdivision | MT0005118 | CWS | Billings | 188 | Yellowstone County |
| Stillwater East Boulder | MT0003894 | NTNCWS | Big Timber | 380 | Sweet Grass County |
| Stillwater Christian School | MT0001742 | NTNCWS | Kalispell | 350 | Flathead County |
| Stillwater Estates County W And S Dist | MT0004221 | CWS | Kalispell | 130 | Flathead County |
| Stillwater Mining Company | MT0003587 | NTNCWS | Nye | 630 | Stillwater County |
| Stillwater Water District | MT0000078 | CWS | Kalispell | 85 | Flathead County |
| Stock Farm The | MT0003982 | CWS | Hamilton | 150 | Ravalli County |
| Stockett Water And Sewer Dist | MT0000579 | CWS | Stockett | 210 | Cascade County |
| Stone Creek Subdivision | MT0005183 | CWS | Billings | 378 | Yellowstone County |
| Stone Ridge Water Company | MT0004605 | CWS | Lakeside | 50 | Lake County |
| Stonefield Business Park Water System | MT0005187 | NTNCWS | Belgrade | 146 | Gallatin County |
| Stoneridge Home Owners Association | MT0004449 | CWS | Columbia Falls | 95 | Flathead County |
| Stoney Brook Village Condominium Assoc | MT0004257 | CWS | Clancy | 142 | Jefferson County |
| Storybook Hollow | MT0004519 | NTNCWS | Billings | 70 | Yellowstone County |
| Streeters Corner Water System | MT0004005 | NTNCWS | Bigfork | 50 | Flathead County |
| Strobel Trailer Court | MT0000125 | CWS | Big Timber | 60 | Sweet Grass County |
| Sula Ranger Station | MT0062214 | NTNCWS | Hamilton | 38 | Ravalli County |
| Sun Prairie Water District | MT0000571 | CWS | Great Falls | 350 | Cascade County |
| Sunburst Town Of | MT0000338 | CWS | Sunburst | 459 | Toole County |
| Sundance Subdivision | MT0005056 | CWS | Billings | 378 | Yellowstone County |
| Sunhaven Mobile Home Park | MT0004147 | CWS | Dallas | 160 | Yellowstone County |
| Sunny Brook Colony | MT0005121 | CWS | Choteau | 80 | Chouteau County |
| Sunny Meadows Water And Sewer Dist | MT0001864 | CWS | Missoula | 135 | Missoula County |
| Sunnybrook Acres Hoa | MT0002482 | CWS | E Helena | 50 | Jefferson County |
| Sunrise Terrace No 1 Hoa | MT0000077 | CWS | Kalispell | 85 | Flathead County |
| Sunrise Terrace Subd No 2 | MT0003040 | CWS | Kalispell | 131 | Flathead County |
| Sunset Boulder Mhp Llc | MT0000584 | CWS | Dillon | 45 | Cascade County |
| Sunset Colony Unapproved | MT0005111 | CWS | Roundup | 75 | Musselshell County |
| Sunset Pines | MT0002538 | CWS | Missoula | 55 | Missoula County |
| Sunset West Rsid | MT0001857 | CWS | Missoula | 105 | Missoula County |
| Sunshine Academy Laurel | MT0003955 | NTNCWS | Laurel | 65 | Yellowstone County |
| Sunshine Academy Shepherd | MT0005180 | NTNCWS | Laurel | 80 | Yellowstone County |
| Super One Food Store | MT0004004 | NTNCWS | Stevensville | 1,769 | Ravalli County |
| Superior Town Of | MT0000339 | CWS | Superior | 1,100 | Mineral County |
| Surprise Creek Colony | MT0000391 | CWS | Stanford | 80 | Cascade County, Judith Basin County |
| Swan Ridge Hoa | MT0004770 | CWS | Kalispell | 28 | Flathead County |
| Swan River School Dist 04 | MT0002844 | NTNCWS | Bigfork | 197 | Flathead County |
| Swan Valley Elementary School Dist 33 | MT0002491 | NTNCWS | Condon | 36 | Missoula County |
| Sweetgrass Ranch Subdivision | MT0005002 | CWS | Kalispell | 65 | Flathead County |
| Sweetgrass Water Users Assn | MT0000340 | CWS | Sweet Grass | 100 | Toole County |
| Swlo And Main Office | MT0003624 | NTNCWS | Missoula | 75 | Missoula County |
| Tamarack Court | MT0000368 | CWS | Missoula | 75 | Missoula County |
| Tamarack Woods Hoa Lakeside | MT0003393 | CWS | Kalispell | 180 | Flathead County |
| Tammaro Water Bottling | MT0005086 | NTNCWS | Missoula | 27 | Sanders County |
| Target Range Main School | MT0003763 | NTNCWS | Missoula | 660 | Missoula County |
| Target Range Trailer Court Llc | MT0000367 | CWS | Knoxville | 200 | Missoula County |
| Ten Mile And Pleasant Valley Wua | MT0002005 | CWS | Helena | 750 | Lewis and Clark County |
| Terry High School District No 5 | MT0001612 | NTNCWS | Terry | 133 | Prairie County |
| Teton Adventist Christian School | MT0004747 | NTNCWS | Choteau | 33 | Cascade County, Teton County |
| The Benches | MT0005069 | CWS | Columbia Falls | 123 | Flathead County |
| The Brooks | MT0004995 | NTNCWS | Missoula | 37 | Ravalli County |
| The Falls Mobile Home Community | MT0005077 | CWS | El Dorado Hills | 60 | Cascade County |
| The Historic Florence | MT0003924 | NTNCWS | Missoula | 400 | Missoula County |
| The Homestead Chinook Ridge | MT0005158 | CWS | Dallas | 33 | Flathead County |
| The Nines Subdivision | MT0004989 | CWS | Billings | 220 | Yellowstone County |
| Thompson Falls City Of | MT0000341 | CWS | Thompson Falls | 1,950 | Sanders County |
| Thompson Ranchettes Ii | MT0002893 | CWS | Kalispell | 100 | Flathead County |
| Thomson Mobile Home Park | MT0000037 | CWS | Bozeman | 65 | Gallatin County |
| Thorpe Commercial Center North | MT0005132 | NTNCWS | Bozeman | 288 | Gallatin County, Meagher County |
| Thorpe Commercial Center South | MT0005133 | NTNCWS | Bozeman | 264 | Gallatin County |
| Three Forks City Of | MT0000343 | CWS | Three Forks | 1,900 | Gallatin County |
| Tiber County Water District | MT0000400 | CWS | Brady | 750 | Chouteau County, Liberty County, Pondera County |
| Timber Ridge Hoa | MT0004939 | CWS | Columbia Falls | 30 | Flathead County |
| Timbers At Whitefish The | MT0004657 | CWS | Bigfork | 40 | Flathead County |
| Torgersons Equipment G Falls | MT0004846 | NTNCWS | Great Falls | 69 | Cascade County |
| Town Pump Belgrade 4 | MT0004860 | NTNCWS | Butte | 730 | Gallatin County |
| Town Pump Bonner 1 | MT0002466 | NTNCWS | Butte | 2,478 | Missoula County |
| Town Pump Lolo 2 | MT0000815 | NTNCWS | Butte | 1,156 | Missoula County |
| Town Pump Three Forks 1 | MT0002034 | NTNCWS | Butte | 1,921 | Broadwater County |
| Town Pump Missoula 7 Wye | MT0004711 | NTNCWS | Butte | 935 | Missoula County |
| Town View Estates Wua Inc | MT0002172 | CWS | Helena | 175 | Lewis and Clark County |
| Townsend City Of | MT0000344 | CWS | Townsend | 2,000 | Broadwater County |
| Tracy Water Users Corp | MT0000345 | CWS | Sand Coulee | 200 | Cascade County |
| Trails End Tr Park Helena | MT0000605 | CWS | Helena | 35 | Lewis and Clark County |
| Trapper Creek Job Corps | MT0062207 | CWS | Darby | 275 | Ravalli County |
| Travois Village Mobile Park | MT0003909 | CWS | Missoula | 702 | Missoula County |
| Treasure State Acres Wua | MT0002390 | CWS | Helena | 483 | Lewis and Clark County |
| Trego School Dist 53 | MT0001170 | NTNCWS | Trego | 47 | Lincoln County |
| Trestle Creek I And Ii | MT0004423 | CWS | Missoula | 110 | Mineral County |
| Tri County Water District | MT0002912 | CWS | Power | 470 | Cascade County, Chouteau County, Teton County |
| Tri Hil Wua Gore Hill | MT0002805 | NTNCWS | Great Falls | 100 | Cascade County |
| Trinity School District #4 In L & C Co | MT0005173 | NTNCWS | Canyon Creek | 50 | Lewis and Clark County |
| Triple Creek Ranch | MT0003687 | NTNCWS | Darby | 120 | Ravalli County |
| Troy City Of | MT0000348 | CWS | Troy | 2,100 | Lincoln County |
| Troy Ranger Station | MT0062350 | NTNCWS | Troy | 282 | Lincoln County |
| Turah Meadows | MT0004537 | CWS | Missoula | 73 | Missoula County |
| Turner Colony | MT0001772 | CWS | Turner | 50 | Blaine County |
| Turner School District No 43 | MT0000723 | NTNCWS | Turner | 97 | Blaine County |
| Turning Winds | MT0004486 | CWS | Meridian | 50 | Lincoln County |
| Turtle Lake Water System | 083090032 | CWS | Pablo | 225 | Lake County |
| Twin Acres Trailer Court | MT0001745 | CWS | Stevensville | 60 | Flathead County |
| Twin Bridges Town Of | MT0000349 | CWS | Twin Bridges | 424 | Madison County |
| Twin Hills Colony Inc | MT0003978 | CWS | Carter | 78 | Chouteau County |
| Two Buttes Water Users Assn | MT0000580 | CWS | Fort Shaw | 525 | Cascade County |
| Two Dot Water Users Company | MT0000586 | CWS | Two Dot | 50 | Wheatland County |
| Two Medicine Water - East Glacier | 083090090 | CWS | Browning | 1,504 | Glacier County |
| Two Mile Tract Hoa | MT0003328 | CWS | Kalispell | 128 | Flathead County |
| Two Rivers Mobile Hm Pk Lolo | MT0000489 | CWS | Missoula | 138 | Missoula County |
| Ulm School Dist 85 | MT0000765 | NTNCWS | Ulm | 94 | Cascade County |
| University Of Providence | MT0004813 | NTNCWS | Great Falls | 1,472 | Cascade County |
| Ups Glendive | MT0005063 | NTNCWS | Seattle | 30 | Dawson County |
| Va Medical Center Helena | MT0000246 | CWS | Fort Harrison | 1,275 | Lewis and Clark County |
| Vaeroy Enterprises, Inc | MT0005079 | NTNCWS | Missoula | 35 | Missoula County |
| Valier Town Of | MT0000351 | CWS | Valier | 452 | Pondera County |
| Valley Christian Cafeteria | MT0003879 | NTNCWS | Missoula | 1,146 | Missoula County |
| Valley Christian School North | MT0003878 | NTNCWS | Missoula | 350 | Missoula County |
| Valley Garden Golf Village Hoa | MT0003597 | CWS | Ennis | 195 | Madison County |
| Valley Grove Subdivision | MT0003780 | CWS | Belgrade | 825 | Gallatin County |
| Valley Grove Water Users Association | MT0000490 | CWS | Lolo | 30 | Missoula County |
| Valley View Elementary School | 083090311 | NTNCWS | East Polson | 45 | |
| Valley Water System The | MT0004518 | CWS | Stevensville | 82 | Missoula County |
| Valley West Trailer Court | MT0000444 | CWS | Lolo | 115 | Missoula County |
| Vaughn Cascade County Water And Sewer | MT0000352 | CWS | Vaughn | 585 | Cascade County |
| Victor Grade School Pws | MT0004699 | NTNCWS | Victor | 140 | Ravalli County |
| Victor Middle School And High School | MT0002134 | NTNCWS | Victor | 185 | Ravalli County |
| Virginia City Water Dept | MT0000353 | CWS | Virginia City | 1,500 | Madison County |
| Vwa Services | MT0005134 | CWS | Bridger | 93 | Carbon County |
| Wagon Wheel Trailer Village | MT0000379 | CWS | Missoula | 210 | Missoula County |
| Wapiti Acres County Water And Sewer Dist | MT0003774 | CWS | Kalispell | 32 | Flathead County |
| Wards Cove Water Users | MT0003277 | CWS | Hamilton | 45 | Ravalli County |
| Warren School District No 1 | MT0001459 | NTNCWS | Helena | 350 | Lewis and Clark County |
| Water Drop Llc | MT0006002 | CWS | Billings | 100 | Yellowstone County |
| Water Resources Division | MT0003623 | NTNCWS | Missoula | 60 | Missoula County |
| Water Service Inc Trout Creek | MT0000347 | CWS | Trout Creek | 350 | Sanders County |
| Wegner Water Service Hauler | MT0003590 | CWS | Hardin | 50 | Big Horn County |
| Wells Garden Estates | MT0002927 | CWS | Billings | 240 | Yellowstone County |
| West Fork Ranger Station | MT0062222 | NTNCWS | Hamilton | 54 | Ravalli County |
| West Glacier Wua | MT0000356 | CWS | West Glacier | 90 | Flathead County |
| West Mountain Estates | MT0004450 | CWS | Missoula | 125 | Mineral County |
| West Valley Pines Hoa Inc | MT0003414 | CWS | Kalispell | 130 | Flathead County |
| West Valley School District No 1 | MT0000895 | NTNCWS | Kalispell | 650 | Flathead County |
| Westana Mobile Manor Hamilton | MT0000634 | CWS | Billings | 90 | Ravalli County |
| Westby Town Of | MT0000355 | CWS | Westby | 172 | Sheridan County |
| Western Energy Company | MT0003840 | NTNCWS | Colstrip | 200 | Rosebud County |
| Western Mobile Village Dillon | MT0002171 | CWS | Alder | 75 | Beaverhead County |
| Western Skies Mobile Ct | MT0000519 | CWS | Helena | 25 | Lewis and Clark County |
| Westview Mobile Home Park | MT0000437 | CWS | Missoula | 947 | Missoula County |
| Wettington Water District Inc | MT0004083 | CWS | Kalispell | 119 | Flathead County |
| Weyerhaeuser Mdf | MT0000917 | NTNCWS | Seattle | 34 | Flathead County |
| Wheat Montana At Muralts Travel Plaza | MT0000847 | NTNCWS | Missoula | 1,225 | Missoula County |
| Wheat Montana Bakery | MT0003700 | NTNCWS | Three Forks | 2,453 | Broadwater County |
| Whispering Pines Tr Ct | MT0001851 | CWS | Port Angeles | 55 | Mineral County |
| Whispering Trees Mobile Park | MT0000408 | CWS | Stevensville | 100 | Dawson County |
| White Bird Community The | MT0000506 | CWS | Stevensville | 82 | Ravalli County |
| White Sulphur Springs City Of | MT0000360 | CWS | White Sulphur Springs | 1,000 | Meagher County |
| Whitefish Hills Village | MT0004940 | CWS | Columbia Falls | 50 | Flathead County |
| Whitefish River Ranch | MT0004660 | CWS | Kalispell | 38 | Flathead County |
| Whitehall Town Of | MT0000359 | CWS | Whitehall | 1,500 | Jefferson County |
| Whitewater Park Assoc Bonner | MT0001865 | CWS | Potomac | 25 | Missoula County |
| Whitewater School Dist 20Aa D | MT0002062 | NTNCWS | Whitewater | 125 | Phillips County |
| Wibaux Town Of | MT0000361 | CWS | Wibuax | 550 | Wibaux County |
| Wild Flower Hoa The | MT0004533 | CWS | Hamilton | 120 | Ravalli County |
| Wilderness Club The | MT0004748 | CWS | Eureka | 440 | Lincoln County |
| Wilderness Plateau Water And Sewer Dist | MT0002985 | CWS | Troy | 208 | Lincoln County |
| Willow Creek School Dist No 15 | MT0001362 | NTNCWS | Willow Creek | 60 | Gallatin County |
| Willow Glen Trailer Court Kspl | MT0000098 | CWS | Stevensville | 69 | Flathead County |
| Wilsall Water District | MT0000362 | CWS | Wilsall | 250 | Park County |
| Windmill Trailer Park Well 1 | MT0000474 | CWS | Livingston | 110 | Park County |
| Windmill Trailer Park Well 2 | MT0000475 | CWS | Livingston | 125 | Park County |
| Windsor Estates | MT0003807 | CWS | Lincoln | 530 | Yellowstone County |
| Windy Acres Wua | MT0002806 | CWS | Great Falls | 50 | Cascade County |
| Winifred Town Of | MT0000363 | CWS | Winifred | 274 | Fergus County |
| Winnett Town Of | MT0000364 | CWS | Winnett | 187 | Petroleum County |
| Wolf Creek Water System | 084690483 | CWS | Pine Ridge | 65 | Lewis and Clark County |
| Wolf Point City Of | 083090058 | CWS | Wolf Point | 3,000 | Roosevelt County |
| Wood Ridge Hoa | MT0004220 | CWS | Bigfork | 70 | Flathead County |
| Woodcock Water System | 083090033 | CWS | Pablo | 101 | Lake County |
| Woodlands Subdivision | MT0005165 | CWS | Eureka | 45 | Flathead County |
| Woodman School District 18 | MT0003731 | NTNCWS | Lolo | 36 | Missoula County |
| Woods Bay Water And Sewer District | MT0004698 | CWS | Bigfork | 685 | Lake County |
| Woodside Park County Water And Sewer Dis | MT0002986 | CWS | Thompson Falls | 115 | Sanders County |
| Woody Mountain Residential Community | MT0005050 | CWS | Missoula | 25 | Missoula County |
| Worden Ballantine Yellowstone | MT0000022 | CWS | Ballantine | 800 | Yellowstone County |
| Wye Area Water System | MT0004107 | CWS | Missoula | 512 | Missoula County |
| Wye Properties, Llc | MT0004138 | NTNCWS | Missoula | 55 | Missoula County |
| Wylie Creek Estates Subdivision | MT0003961 | CWS | Bozeman | 400 | Gallatin County |
| Wyola Water System | 083090014 | CWS | Crow Agency | 281 | Big Horn County |
| Yellowstone Boys And Girls Ranch | MT0000154 | CWS | Billings | 240 | Yellowstone County |
| Yellowstone Commercial Center | MT0004972 | NTNCWS | Manhattan | 400 | Gallatin County |
| Yellowstone Holiday Wtr And Sew District | MT0001326 | CWS | West Yellowstone | 85 | Gallatin County |
| Yellowstone Ice And Water Unapproved | MT0003996 | NTNCWS | Billings | 61 | Yellowstone County |
| Yellowtail Dam Gc System | MT0002514 | CWS | Yellowtail | 125 | Big Horn County |
| Youth With A Mission | MT0003262 | CWS | Lakeside | 150 | Flathead County |
| Zenith Colony | MT0004768 | CWS | Cut Bank | 70 | Glacier County |
| Zurich School District 17 | MT0000729 | NTNCWS | Zurich | 26 | Blaine County |