Explainer · proposed rule
PFOA and PFOS limits: the 2029 deadline and the 2031 proposal
EPA’s limits for PFOA and PFOS in drinking water are 4.0 parts per trillion each, with compliance due in April 2029. A proposal published on May 20, 2026 would let eligible water systems request exemptions until April 2031. It is not final.
A clearer perspective.The limits themselves do not change
The proposal keeps the Maximum Contaminant Levels at 4.0 ppt for PFOA and 4.0 ppt for PFOS. Compliance is judged on running annual averages, which is why this site compares UCMR 5 results on the average of a complete sampling set, not on a single sample.
What the proposal would do
- Published: Federal Register, May 20, 2026 (document 2026-10086), docket EPA-HQ-OW-2025-1742.
- Change: eligible systems could receive an exemption moving their compliance date from April 2029 to April 2031. It is a request-and-approval process, not an automatic delay for every utility.
- Condition: systems with PFOA or PFOS at or above 12 ppt would have to take short-term mitigation steps during the exemption, and systems would tell customers through public notices and their annual water report.
- Comment period: a virtual public hearing was held on July 7, 2026, and comments closed on July 20, 2026.
A separate EPA proposal would rescind the limits for PFHxS, PFNA, HFPO-DA (GenX) and certain PFAS mixtures. Both are proposals; neither changes a limit until EPA publishes a final rule.
What it means for you
Until a final rule appears, the 2029 date stands. If your utility found PFOA or PFOS in EPA’s survey, its annual report and public notices are where you will learn whether it applies for more time and what it does in the meantime. See PFOA and PFOS for the national survey results, and our note on both proposals.