What contaminants are in London tap water?

The most commonly flagged contaminants across London are Nitrite (flagged in 50 areas), Coliform Bacteria (flagged in 13 areas), E. coli (flagged in 2 areas), Fluoride (flagged in 1 area). No PFAS were detected.

England

Is London tap water safe to drink?

Q: Is London tap water safe to drink?

Yes, London tap water is generally safe to drink. Across 53 areas tested, the average water quality score is 8.4/10. The capital serves over 9 million people through Thames Water, one of the UK's largest water suppliers.

Q: Who supplies water in London?

Water in London is supplied by Thames Water. The capital serves over 9 million people through Thames Water, one of the UK's largest water suppliers.

The capital serves over 9 million people through Thames Water, one of the UK's largest water suppliers.

Average score

8.4/10

Areas tested

Issues flagged

PFAS detected

None

Yes, London tap water is safe to drink. Based on 53 areas tested, London has an average water quality score of 8.4/10. 69 contaminants were flagged above recommended levels across all areas. Water is supplied by Thames Water. The capital serves over 9 million people through Thames Water, one of the UK's largest water suppliers.

Top concerns in London

Contaminants flagged most often across the city.

Nitrite50 areas

Coliform Bacteria13 areas

E. coli2 areas

Fluoride1 area

Iron1 area

Lead1 area

Water quality by area

All postcode districts in London, ranked by water quality score.

PostcodeAreaScoreFlaggedSupplier

SE1Southwark7.13Thames Water NW1Westminster7.23Thames Water HA8Barnet7.42Thames Water E2Hackney7.81Thames Water E8Hackney7.81Thames Water N16Hackney7.82Thames Water N5Hackney7.82Thames Water W14Hammersmith and Fulham7.82Thames Water BR7Greenwich7.92Thames Water E1Hackney8.01Thames Water E14Tower Hamlets8.01Thames Water NW9Barnet8.02Thames Water SW10Hammersmith and Fulham8.02Thames Water SW1AWestminster8.02Thames Water SW3Westminster8.02Thames Water SW5Kensington and Chelsea8.02Thames Water SW6Hammersmith and Fulham8.02Thames Water W10Westminster8.02Thames Water SE16Southwark8.12Thames Water E15Hackney8.21Thames Water E20Hackney8.21Thames Water E5Hackney8.21Thames Water E9Hackney8.21Thames Water SE13Greenwich8.31Thames Water SE23Southwark8.42Thames Water N1Camden8.51Thames Water N15Hackney8.51Thames Water NW8Westminster8.51Thames Water N10Barnet8.61Thames Water N4Hackney8.61Thames Water N7Camden8.61Thames Water NW11Barnet8.61Thames Water NW2Barnet8.61Thames Water NW5Camden8.61Thames Water N19Camden8.71Thames Water NW10Hammersmith and Fulham8.71Thames Water NW3Barnet8.71Thames Water NW6Westminster8.71Thames Water SE10Greenwich8.71Thames Water SE18Greenwich8.71Thames Water SE22Southwark8.71Thames Water SE5Southwark8.71Thames Water SW1VWestminster8.71Thames Water SW7Westminster8.71Thames Water W11Westminster8.71Thames Water W12Hammersmith and Fulham8.71Thames Water W2Westminster8.71Thames Water W8Kensington and Chelsea8.71Thames Water W9Westminster8.71Thames Water SE15Southwark8.81Thames Water SE3Greenwich8.81Thames Water DA15Greenwich9.60Thames Water DA16Greenwich9.60Thames Water

Main water supplier

Thames Water

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