What does the Water Bill Calculator do?

Estimate your annual water bill for metered or unmetered supply including sewerage charges. All calculations are performed in your browser using official UK rates and thresholds.

Does this reflect the current energy price cap?

This calculator uses representative energy prices. The Ofgem energy price cap changes quarterly — check Ofgem's website for the latest cap level applicable to your region and payment method.

Can I save money by switching tariff?

Potentially yes. The energy market offers various fixed and variable tariffs. Use a comparison site authorised by Ofgem (such as Ofgem's own comparison tool) to check if switching could save you money.

Water Bill Calculator

Estimate your annual water bill for metered or unmetered supply including sewerage charges.

Last updated: April 2026 · Source: GOV.UK — Check your water bill

People in Household

Average usage: 145 litres/person/day

Estimated Annual Water Bill

£687.47

£57.29/month

Water Supply

£321.27

Sewerage

£366.20

Estimated usage: 435 litres/day (159 m³/year)

Rates are UK averages — your water company may charge differently.

Disclaimer

This calculator is provided for informational purposes only and should not be considered as financial or tax advice. All calculations are performed locally in your browser — no personal data is collected or sent to our servers. Rates and thresholds are sourced from HMRC and GOV.UK and are updated for the current tax year. Always verify results with HMRC or consult a qualified professional before making financial decisions.

How It Works

UK water bills are charged either on a metered basis (paying for what you use) or an unmetered basis (based on your property's rateable value). Metered charges consist of a standing charge plus a rate per cubic metre of water used and a separate rate for sewerage. The average metered household bill is approximately £448 per year.

Whether a meter saves you money depends on your household size and usage. As a rule of thumb, if the number of bedrooms in your home exceeds the number of occupants, a water meter is likely to save you money. Single occupants in large houses benefit most from switching to a meter.

You have a right to request a free water meter installation. If a meter cannot be fitted, you may be offered an assessed charge based on average usage for your household size. This calculator compares your estimated bill on both metered and unmetered charges to show which option is cheaper for your situation.

Example: 2-person household, 3-bed house

Average water usage: 280 litres/day (140 per person)
Annual usage: 102.2 cubic metres
Metered water charge: 102.2 x £1.85 = £189.07
Metered sewerage: 102.2 x £1.95 = £199.29
Standing charges: £84/year
Total metered bill: £472/year

Source: GOV.UK — Check your water bill

Frequently Asked Questions

What does the Water Bill Calculator do?: Estimate your annual water bill for metered or unmetered supply including sewerage charges. All calculations are performed in your browser using official UK rates and thresholds.
Does this reflect the current energy price cap?: This calculator uses representative energy prices. The Ofgem energy price cap changes quarterly — check Ofgem's website for the latest cap level applicable to your region and payment method.
Can I save money by switching tariff?: Potentially yes. The energy market offers various fixed and variable tariffs. Use a comparison site authorised by Ofgem (such as Ofgem's own comparison tool) to check if switching could save you money.