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Household Bills & Lifestyle2 min check

Energy Bill Calculator

Estimate your annual gas and electricity bill using your usage in kWh and indicative Ofgem cap rates.

Short answer

Bill = (electricity kWh × unit rate) + (gas kWh × unit rate) + (standing charges × 365 days). We use indicative 2025 cap averages — your actual rates depend on tariff and region.
Step 1 of 10%

Your usage

Payment method

How it works

Annual cost = (kWh × p per kWh ÷ 100) + (standing charge p/day × 365 ÷ 100). Add gas and electricity. Standard credit (paying on the bill) adds about 6% to direct-debit rates.

Worked example

2,700 kWh elec at 27p + 60p/day standing + 11,500 kWh gas at 6.5p + 32p/day → £729 + £219 + £747.5 + £116.8 ≈ £1,812/year.

Who should use this

  • Households comparing tariffs
  • Anyone budgeting after a price cap change
  • Tenants splitting bills

Common mistakes

  • ×Forgetting standing charges
  • ×Mixing pence and pounds (rates are in pence per kWh)
  • ×Using monthly figures instead of annual kWh

Frequently asked questions

Where do I find my unit rate?

On any recent bill or your online account — listed as 'unit rate' in p/kWh and 'standing charge' in p/day.

How is the price cap set?

Ofgem updates the cap every 3 months based on wholesale costs, network charges and supplier margins.

Is a fixed tariff cheaper?

Sometimes — when wholesale prices are expected to rise. Check the fix vs current cap and any exit fees.

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