Is there PFAS in UK drinking water?

What this page can tell you, and what it cannot

This page states the figures a regulator here publishes for this family of chemicals, in the words it published them in, and says which parts of the country each one is about. Every figure below carries the body that set it, the document it is set in and the day this site read that document.

What it does not carry is a result for your own supply. Nothing this project has verified publishes those in bulk, and the section that says so names what was looked for and where, so the claim can be checked rather than believed.

Why a guidance value is not the same as a limit in law

A regulator can publish a figure it expects water companies to work to without that figure being a standard written into the regulations. The two read the same on a page and mean different things: one is enforceable in its own right, the other is the regulator's own expectation, and a site that printed only the number would have quietly turned the second into the first.

So each figure here is marked as one or the other, and the passage it was read from is printed underneath it in full. Where a body publishes no figure at all, this page says that instead of finding a substitute somewhere else.

Why a figure from another country is not an answer here

Different countries have set very different numbers for these substances, and the arithmetic between them is not a conversion — it is a different assessment, made by a different body, under a different law. Putting one country's figure on another country's page is the fastest way to publish something that is precise and wrong.

Every figure on this page was read from a document about this country. Where a document covers only part of it, the part is named, and the parts it does not cover are listed underneath with the reason nothing is held for them.

Where the words on this page come from

Everything inside quotation marks was transcribed from a page or a report that this site opened on a stated day, and the body it was transcribed from is committed alongside the code so each sentence can be checked against it without trusting anybody.

Everything outside quotation marks is either a figure with its own source beside it, or a sentence about how the page was put together. There is no advice here, and there is nothing here about what to buy.

The figures this country publishes

Where PFAS stands here, in the regulator's own words

Which parts of the country this covers

Everything above was read from documents about England and Wales.

Who monitors it, and what a resident can do

Why there is no table of results on this page

What was looked for: a per-system PFAS result for this country — a concentration, with the supply system it was measured in and the date the sample was taken. Where: the Environment Agency's water quality archive and the Drinking Water Inspectorate's PFAS monitoring publications, neither of which has yet been confirmed to publish per-site PFAS results in bulk, and the water industry's shared data portal, whose drinking water quality datasets this site already reads.

What it says instead: “The Drinking Water Inspectorate (DWI) is currently engaged with water companies in England and Wales to improve knowledge about the location, types and levels of specific PFAS.”

What would change this: a check, made before anything is read from them, of whether those publications give per-site PFAS results in bulk and under what licence. Until that check is recorded and the names of the substances measured are reviewed, this page publishes the limits and states no result of its own.

Source: Drinking Water Inspectorate — PFAS and Forever Chemicals — read 21 September 2026

What is published elsewhere, and why it is not here

More on water quality here

• What we hold on tap-water safety, town by town
• Every water company, and what we hold for it