What are the biggest cost drivers at home?

Space heating, hot water, electric resistance heating, and long-hour appliances tend to dominate costs in many homes.

Calculator

Home Energy Cost Calculator

Get a quick view of monthly electricity, heating, annual spend, and the habits or loads that may be driving your bills.

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Build a quick energy-cost baseline for your home

This page helps you turn a few headline assumptions into a simple household energy estimate. It is a useful first step if you want to see whether heating demand, hot water, or appliance use is likely driving your bills.

Use the result to spot priorities, then compare it with real bills before deciding which upgrade or behavior change comes first.

How the formula works

Monthly electricity estimate combines appliance kWh and hot water kWh multiplied by the electricity price.

Monthly heating estimate uses annual heating demand divided by 12, multiplied by the selected heating fuel price.

Example calculation

If appliances use 260 kWh per month and hot water uses 120 kWh per month at 27p per kWh, monthly electricity cost is about GBP103.

If annual heating demand is 12,000 kWh and gas costs 7p per kWh, monthly heating energy is about GBP70 before standing charges.

Country or regionHeating fuel used for space heatingElectricity priceGas priceOil priceAppliance usage per month in kWhAnnual heating demandHot water usage per month in kWh

United Kingdom assumptions

Currency: GBP. Electricity: Check current official sources. Gas: Check current official sources. Heating oil: Check current official sources.

Last reviewed: 2026-04-27. Confidence: medium. Prices are not pre-filled because supplier tariffs and price caps change. Enter your current unit rates from a bill.

Monthly electricity estimate

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Monthly heating estimate

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Annual energy estimate

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Biggest cost drivers

Space heating demand, High-usage appliances, Tariff structure

Savings tips

Reduce standby and long-run appliance use before buying new hardware. Improve insulation and controls to lower peak heating demand. Benchmark big loads like tumble dryer and portable heaters first.

Planning note

12,000 kWh annual heat demand currently assumed using gas pricing for heating.

Calculators on this site are estimates only. Always get a professional heat loss survey and verify current grant rules, tariffs, and product suitability before making purchase decisions.

Home energy cost FAQs

The tool focuses on variable energy use rather than supplier standing charges. Add those separately if you want a closer total bill estimate.

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