Is there PFAS in your
tap water?
Enter your ZIP code to see what EPA's national testing program found in your local water utility — what was detected, at what levels, and what (if anything) is worth doing about it.
Free. No account needed. Data from EPA UCMR 5 (updated Jan 2026).
"Forever chemicals" that don't break down in your body or the environment
Per- and polyfluoroalkyl substances (PFAS) are a family of more than 12,000 synthetic chemicals used since the 1940s — non-stick cookware, waterproof clothing, food packaging, firefighting foam, and a long list of industrial processes.
They're sometimes called "forever chemicals" because they don't break down easily, so they accumulate in water, soil, and the human body over time. Long-term exposure to higher levels has been linked in research to several health concerns. The point of this site is to show you what the data says about your specific water — so you can decide what, if anything, to do about it.
Learn about each PFAS compound →What the Research Has Linked PFAS To
PFAS exposure is cumulative — it builds up in the body over years rather than causing acute effects. The conditions below have been associated with higher PFAS exposure in peer-reviewed studies. Reducing exposure where it's easy (like at the tap) is a reasonable precaution; panic isn't.
Cancer Risk
- Kidney cancer
- Testicular cancer
- Bladder cancer
Thyroid & Hormones
- Thyroid disease
- Hormone disruption
- Metabolic disorders
Immune Suppression
- Weakened vaccine response
- Increased infections
- Autoimmune conditions
Child Development
- Low birth weight
- Developmental delays
- Earlier puberty onset
Sources: EPA, NIH National Toxicology Program, ATSDR, peer-reviewed studies in Environmental Health Perspectives
How PFAS Gets Into Drinking Water
PFAS contamination follows predictable patterns. Understanding the sources helps explain why some communities face much higher risk than others.
Industrial Manufacturing
Major SourceFacilities producing non-stick coatings, semiconductors, and fluoropolymers discharge PFAS into nearby waterways and groundwater. Major contamination hotspots exist around legacy manufacturing plants in states like NC, WV, and MN.
Military Bases & Airports
Major SourceAqueous film-forming foam (AFFF) used in fire training exercises and emergencies has saturated groundwater at hundreds of military installations and civilian airports. The DoD has identified over 700 contaminated sites.
Consumer Products & Landfills
Diffuse SourcePFAS from stain-resistant carpets, waterproof clothing, food packaging, and cookware accumulates in landfills. Leachate from these landfills can migrate into groundwater over time, especially in older, unlined sites.
Sewage Sludge (Biosolids)
Emerging ConcernPFAS-laden biosolids (treated sewage) spread on farmland as fertilizer have contaminated soil and groundwater across rural America, impacting private wells and small water systems far from any industrial site.
Most Affected States
Explore Contamination Across the Entire Country
Every US county colored by its maximum detected PFAS concentration, powered by EPA's UCMR 5 dataset. Click any county to see its ZIP codes, testing results, and jump to state-level detail.
View the National HeatmapPFAS News, Guides & Research
PFAS in Private Wells: A Plain-English Testing Guide
EPA's drinking-water rules don't cover private wells, so testing is on you. Here's what to ask for, what it costs, and how to interpret the results — without panic.
How to Read Your Water Utility's Annual Consumer Confidence Report
Every public water utility in the US has to publish an annual Consumer Confidence Report. Here's how to find yours, what each section actually means, and what to look for if PFAS is a concern.
Where the EPA PFAS Drinking Water Rule Stands in 2026
The EPA's PFAS Maximum Contaminant Levels were finalized in April 2024, with monitoring compliance due in 2027 and treatment compliance in 2029. Here's where things actually stand and what it means for your water.
What You Can Actually Do About PFAS
Most of what you read about PFAS is either alarmist or vague. Here are five concrete, proportional steps — ordered from "free and 5 minutes" to "longer-term" — that meaningfully reduce your exposure.
- 1
See what's actually in your water
Start with the data. Enter your ZIP code above, or browse the national heatmap, then read your utility's most recent Consumer Confidence Report (mailed or posted annually). Knowing whether you have a real exposure issue avoids buying gear you don't need.
Free · 5 minutes
- 2
If levels concern you, filter at the tap
Two filter technologies reliably remove PFAS at home: reverse osmosis (under-sink, ~$200–$600) and activated carbon block (pitcher or under-sink, ~$30–$200). Look specifically for NSF/ANSI 53 or NSF/ANSI 58 certification with "PFOA & PFOS reduction" listed on the certification sheet — generic Brita/PUR pitchers are typically not certified for PFAS.
- 3
Cut a few of the other exposure routes
Drinking water is one input among many. Easy wins that don't require buying anything new: skip greaseproof fast-food wrappers and microwave popcorn bags (often PFAS-coated), avoid stain-resistant carpet treatments, replace badly scratched non-stick pans, and choose PFAS-free dental floss and waterproof outerwear when you do replace them. You don't need to do all of these — pick whichever fit your routine.
- 4
If you're on a private well, get it tested
The EPA's PFAS rule and the data on this site only cover public water systems — not private wells. A certified lab running EPA Method 537.1 can test for the regulated PFAS compounds for around $300–$500. Your state's environmental agency typically maintains a list of certified labs.
- 5
Watch your utility's progress, not the news cycle
Public water systems have until 2029 to install treatment if PFAS levels exceed the EPA MCL. Most large utilities now publish their PFAS treatment plans in public board materials. The stories that make headlines often aren't your local situation; reading your own utility's planning documents is far more useful.
This isn't medical advice. If you've been drinking water with PFAS above the MCL for years and want a clinical evaluation, the ATSDR's PFAS clinical guidance is the standard reference clinicians use.
PFAS in Drinking Water — Common Questions
What are PFAS?
PFAS (per- and polyfluoroalkyl substances) are a family of more than 12,000 man-made chemicals used since the 1940s in non-stick cookware, waterproof clothing, food packaging, and firefighting foam. They're called "forever chemicals" because they don't break down in the environment or in the human body. PFAS contaminate drinking water for an estimated 200 million Americans.
Are PFAS in my tap water?
Possibly. EPA's UCMR 5 testing detected at least one PFAS compound at the majority of public water systems sampled. To check yours, enter your ZIP code at checkpfas.com — our data covers roughly 10,000 public water systems and the ~14,000 ZIP codes where those systems were tested.
What is the EPA's PFAS limit in drinking water?
EPA finalized Maximum Contaminant Levels (MCLs) in April 2024: 4 parts per trillion (ppt) each for PFOA and PFOS, plus 10 ppt each for PFHxS, PFNA, and HFPO-DA (GenX). Public water systems have until 2027 to complete monitoring and 2029 to install treatment if any MCL is exceeded. EPA announced a reconsideration of the four 10 ppt limits in May 2025; the PFOA and PFOS limits are stable.
How can I remove PFAS from my drinking water?
Three filter technologies are proven effective at home: granular activated carbon (GAC), reverse osmosis (RO), and ion exchange. Look for filters certified to NSF/ANSI 53 or NSF/ANSI 58 specifically for PFOA/PFOS reduction. Standard pitcher and refrigerator filters typically do NOT remove PFAS unless explicitly certified.
What health risks do PFAS pose?
Long-term PFAS exposure is linked to increased risk of kidney and testicular cancer, thyroid disease, high cholesterol, immune-system suppression, decreased vaccine response, ulcerative colitis, pregnancy-induced hypertension, and lower birth weight. Children, pregnant women, and those drinking contaminated water for years face the highest risk.
Is bottled water free of PFAS?
Not necessarily. Independent testing has detected PFAS in many bottled water brands, sometimes at levels comparable to tap water. The FDA does not currently require PFAS testing for bottled water. A certified home filter is generally a more reliable and cost-effective solution.
How CheckPFAS Works
EPA Source Data
All data comes directly from EPA's UCMR 5 — the most comprehensive PFAS testing ever conducted on US public water systems.
ZIP → Water System Mapping
We map every US ZIP code to its corresponding public water utility using official EPA service area data.
Plain-English Results
Chemical acronyms translated to plain language — with EPA limit comparisons and certified filter recommendations. Glossary of terms →
What Do These Terms Mean?
Water quality reports are full of acronyms. Here are the four you'll see most often on CheckPFAS.
The EPA's legal limit for a contaminant in tap water. Water utilities must act — and tell you — if this level is exceeded.
How PFAS concentration is measured. 4 ppt = 4 drops of water in 250 Olympic swimming pools — tiny amounts with real health effects.
"Forever chemicals" — 12,000+ synthetic compounds that don't break down in water, soil, or the human body.
The 2023–2025 program that tested 10,000+ water systems for 29 PFAS compounds. Every result on this site comes from UCMR 5.
Find out what's in your water
Free. Takes 5 seconds. Data from 10,000+ water utilities nationwide.