Is Montana Tap Water Safe to Drink?
Water quality data for 8 cities across Montana. Find your city below.
Water quality in Montana varies significantly from city to city. Across 8 cities we track, hardness ranges from 16 PPM in Missoula to 160 PPM in Helena, with a statewide average of 74 PPM. 1 of 8 cities have hard water above 120 PPM where a water softener provides measurable benefits.
1 Montana cities have forever chemicals (PFAS) above the EPA's 2024 limit of 4 parts per trillion: Kalispell (10.9 ppt). A reverse osmosis system or NSF P473-certified filter can reduce PFAS to safe levels.
Complete Montana Guide
Statewide water quality overview, costs, and treatment recommendations.
Well Water in Montana
Testing, treatment, and common issues for private wells.
Hardest Water Rankings
Montana cities ranked by water hardness level.
City Comparisons
Helena vs Missoula
Side-by-side water quality comparison.
Helena vs Havre
Side-by-side water quality comparison.
Havre vs Bozeman
Side-by-side water quality comparison.
Montana Cities by Water Hardness
| City | Hardness (PPM) | Level | PFAS (ppt) | Source |
|---|---|---|---|---|
| Helena | 160 | Hard | 0 | Missouri River + Ten Mile Creek |
| Havre | 110 | Moderately Hard | 0 | Fresno Reservoir (Milk River) |
| Bozeman | 79 | Moderately Hard | 0 | Hyalite Reservoir, groundwater |
| Great Falls | 71 | Moderately Hard | 0 | Missouri River |
| Billings | 65 | Moderately Hard | 0 | Yellowstone River |
| Butte | 55 | Slightly Hard | 0 | Basin Creek & Moulton Reservoir |
| Kalispell | 35 | Slightly Hard | 10.9 | Ashley Lake & Whitefish Lake |
| Missoula | 16 | Soft | 0 | Rattlesnake Creek, groundwater |