Energy Bill Calculator UK
This energy bill calculator helps you estimate UK electricity and gas costs using annual usage, unit rates and standing charges. It is useful for households comparing tariffs, budgeting for a move, checking quoted rates, or turning yearly usage into a more practical monthly estimate.
If you want a quick view of likely annual, monthly or weekly costs before committing to a tariff, this tool gives you a simple planning estimate without needing a full supplier bill.
What this calculator includes
- Annual electricity usage in kWh
- Annual gas usage in kWh
- Electricity and gas unit rates
- Electricity and gas standing charges
- Weekly, monthly and annual energy cost estimates
- Support for electricity-only homes by setting gas values to zero
How it works
The calculator multiplies your yearly electricity and gas usage by the unit rates you enter. It then adds the daily standing charges across the number of days selected to estimate the total cost.
This produces a rough annual figure, which can then be viewed as a monthly or weekly estimate. It is a straightforward way to compare tariffs and sense-check whether a quoted rate looks competitive.
Why your results may be different
Real energy bills can differ from an estimate because suppliers may smooth payments over the year, apply discounts or credits, change tariffs part-way through a billing period, or use regional pricing. Your actual usage may also rise or fall depending on weather, occupancy and heating habits.
Who this calculator is for
- Households comparing electricity and gas tariffs
- People budgeting before moving home
- Anyone turning annual usage figures into monthly cost estimates
- Renters or buyers checking likely running costs before choosing a property
- People reviewing whether a quoted tariff looks reasonable
Energy bill examples
- A lower-usage flat may have modest unit costs but still feel expensive because standing charges make up a larger share of the bill.
- A family home with high gas usage may see winter heating costs dominate the annual total even if electricity use stays stable.
- An all-electric property can be estimated by entering electricity usage only and setting gas usage and gas standing charges to zero.
Important note
This tool provides estimates only and is not financial or energy advice. It does not recreate a supplier bill exactly. Actual bills may differ due to direct debit smoothing, discounts, credits, tariff changes, regional pricing and billing period timing.
Use the calculator above to estimate your energy bill and compare different usage levels or tariff rates.