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%

Calculation method, coverage and version

Inputs used: Electricity used per year (kWh), Gas used per year (kWh), Electricity unit rate (p/kWh), Electricity standing charge (p/day), Gas unit rate (p/kWh), Gas standing charge (p/day), Payment method.
Calculation approach: The calculator applies the rules and assumptions described in “How it works” to the values you enter. Rounding can cause small differences from an official or provider calculation.
Coverage: Household Bills & Lifestyle. UK nations, tax treatment, local rules and provider criteria can differ; check the official sources shown below before acting.
Content version: No page-specific review date is currently published. Treat the result as indicative and verify current rules independently.

Not included unless explicitly requested: personal circumstances not entered, provider discretion, future rule changes, professional fees and case-specific exceptions. Read the full calculator methodology.

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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