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Household Bills & Lifestyle2 min check
Water Bill Calculator
Step 1 of 10%
How it works
We multiply household size by daily usage to get cubic metres per year, then apply your provider's water and sewerage unit rates plus standing charges.
Worked example
4 people × 140 L/day × 365 = 204 m³/year. Severn Trent: (204 × £1.85) + (204 × £2.55) + (£0.65 × 365) ≈ £898/year + £237 = ~£1,135.
Who should use this
- •Households deciding whether to switch to a meter
- •Tenants estimating bills before moving in
- •Anyone tracking water use
Common mistakes
- ×Forgetting sewerage is a separate charge (often more than water)
- ×Using litres in the m³ formula
- ×Ignoring social tariffs and WaterSure if eligible
Frequently asked questions
Should I switch to a water meter?▾
Generally worth it if there are fewer occupants than bedrooms (e.g. 2 people in a 3-bed). You can switch back within 24 months if it's more expensive.
Is sewerage included?▾
Yes — most bills combine water in + waste water out. Some properties on septic tanks pay water only.
How much water does an average UK person use?▾
Around 140 litres per day per person, including showers, toilet, dishwasher, washing machine and cooking.