The forecast average Thames Water household bill is £658 a year from 1 April 2026. That is £3 more than the £655 average for 2025/26.
What your bill includes
The published average combines clean water and wastewater services. A metered bill normally includes fixed charges plus charges linked to measured water and an assessed wastewater volume.
Area and postcode guide
Thames Water serves London and the Thames Valley. Postcode areas commonly associated with its region include E, EC, EN, HA, HP, LU, N, NW, OX, RG, SE, SL, SW, TW, UB, W, WC, but boundaries can divide a postcode and water and wastewater services may come from different companies.
Places in this regional benchmark
Estimate your Thames Water bill
The company average is a benchmark, not a tariff. A one-person metered home that uses water carefully can be well below it. A larger household may be above it. Use the calculator with your household size and a realistic usage level.
Your latest bill and the tariff published by Thames Water are the authoritative sources for your charging zone, fixed charges and meter rates.
Thames Water questions
What is the average Thames Water bill in 2026/27?
Thames Water's published combined water and wastewater household average is £658 a year, equivalent to £54.83 a month. Individual bills vary.
Can I switch away from Thames Water?
Household customers cannot normally switch their appointed regional water company. Eligible businesses in England can choose a water retailer.
Why might my bill be higher than the average?
A larger household, high metered consumption, a leak, a high rateable value or extra services can all result in a higher bill. Compare like with like and check whether your figure covers both water and wastewater.