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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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Published: 2026-01-01

Last updated: 2026-04-28

Last reviewed: 2026-04-28

Confidence: medium

Page review status

Written by: HeatWise Home Editorial Team

Reviewed by: Editorial review by HeatWise Home

Review status: Internally reviewed for clarity, source consistency, and calculation assumptions.

Expert review: Not currently externally expert-reviewed.

Last updated: 2026-04-28

Last reviewed: 2026-04-28

Confidence: medium

Sources:

External expert review: HeatWise Home does not currently publish named external expert reviewers. We are working toward adding independent review from qualified retrofit, heating, or building-energy professionals. Until then, users should treat our calculators and guides as educational planning tools and confirm decisions with official sources and qualified installers.

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.

Helpful next step

See formulas, assumptions, and limits behind each estimate.

Read our calculator methodology

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.

United Kingdom assumptions

Currency: GBP. Electricity: £0.25 per kWh. Gas: £0.06 per kWh. Heating oil: £0.11 per kWh.

  • Planning ranges: Electricity GBP 0.22-0.34 per kWh (Ofgem regional cap spread and available tariffs); Gas GBP 0.05-0.11 per kWh (Ofgem cap benchmark and regional/tariff variation); Heating oil GBP 0.09-0.13 per kWh equivalent (kerosene supplier tracking, delivery-size and season dependent).
  • Last checked: 2026-04-28. Confidence: medium.
  • Sources: Ofgem energy price cap and market data, GOV.UK Boiler Upgrade Scheme, MCS standards and UK building fabric guidance.

Caveat: prices vary by supplier, tariff, region, standing charge, and usage. Electricity/gas benchmarks align with Ofgem's 1 April to 30 June 2026 cap context (24.67p/kWh electricity and 5.74p/kWh gas GB average, Direct Debit) and broader tariff variation. Heating-oil range uses UK supplier-tracked kerosene pricing converted to kWh-equivalent planning values.

View calculator methodology

Monthly electricity estimate

£95

Monthly heating estimate

£60

Annual energy estimate

£1,860

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.

Helpful next step

Adjust fuel prices, SCOP, grants, and costs using your own numbers.

Estimate your heat pump payback

Related tools and guides

Insulation ROI CalculatorAppliance Running Cost CalculatorBest Upgrades for Lower Bills

Methodology and assumptions

Review formulas, SCOP/COP context, fuel price assumptions, and limitations before relying on results.

Read calculator methodology

Request local quotes or guidance

Send a homeowner question, correction, partnership note, or request for help comparing energy upgrades.

Privacy and referral transparency

  • There is no obligation to proceed after you submit this form.
  • We do not routinely share your details with third parties.
  • Partner introductions only happen where relevant to your request.
  • Your data is handled according to our Privacy Policy.

What happens next:

  1. We review your question or quote request.
  2. We may reply directly or ask for missing details.
  3. If a partner introduction is relevant, we explain who the partner is before sharing your details.
  4. You are under no obligation.
  5. Your data is handled according to our Privacy Policy.

If we suggest a partner

Where we suggest a partner, we aim to prioritise relevant, reputable providers or installers. We do not recommend proceeding without checking credentials, quotes, warranties, and official grant requirements.

Get practical energy-saving tips by email

Occasional homeowner-friendly notes on heating costs, grants, insulation, and practical ways to lower bills.

Helpful next step

Pressure-test savings assumptions before committing to upgrades.

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