PFAS Detections in Montana ZIP Codes — 2026

Out of 7 ZIP codes with data in Montana, these are the highest-ranked areas for pfas status. See also: National ZIP Codes with PFAS Detections in Water | All Montana Rankings

Statistic	Value
ZIP codes ranked	7
Highest value	0.0 ppt
Median value	0.0 ppt
State	Montana

Top 7 Worst ZIP Codes

Rank	ZIP Code	City	State	Safety Score
1	59405	Great Falls	MT	56/100
2	59901	Kalispell	MT	62/100
3	59903	Kalispell	MT	63/100
4	59904	Kalispell	MT	63/100
5	59937	Whitefish	MT	65/100
6	59716	Big Sky	MT	70/100
7	59840	Hamilton	MT	70/100

Methodology

PFAS detection data comes from EPA UCMR5 monitoring, state-level testing programs, and Consumer Confidence Reports. ZIP codes are ranked by maximum PFAS concentration detected. The EPA has set MCLs of 4 ppt for PFOA and PFOS individually. PFAS are persistent chemicals that do not break down in the environment.

Data sources: EPA Safe Drinking Water Information System (SDWIS), FEMA National Flood Insurance Program, EPA radon zone maps, EIA electricity rates, and Consumer Confidence Reports. Last updated: 2026-06-04.

Frequently Asked Questions

What are PFAS?

PFAS (per- and polyfluoroalkyl substances) are synthetic chemicals used in non-stick coatings, firefighting foam, and food packaging since the 1940s. They are called "forever chemicals" because they do not break down naturally. PFAS are linked to cancer, liver damage, thyroid disease, and immune system suppression.

How can I remove PFAS from my water?

Reverse osmosis (RO) and granular activated carbon (GAC) filters are effective at removing most PFAS from drinking water. NSF/ANSI 53 or 58 certified filters are recommended. Boiling water does NOT remove PFAS.