Fixed vs variable energy tariff calculator
Should you fix your energy tariff or stay on a variable rate? Enter your current rates and annual usage to see the projected cost difference over 12 months, and how much a fixed deal could save you.
Enter 0 if electricity only
Default: July 2026 price cap
The cheapest fixed electricity rate available is approximately 24p/kWh (June 2026). Enter the rate from a specific deal you are considering.
Approximate cheapest fixed gas rate (June 2026)
Enter any exit fee you would pay to leave your current tariff. Enter 0 if on a variable tariff.
12-month cost comparison
On your current variable rate
£1,863 total | £1,863/year
On the fixed tariff rate
£1,710 total | £1,710/year
Net saving over 12 months
£152
Based on these rates, fixing could save you approximately £152 over 12 months.
See how the cap has changed over time in our price cap history chart, or estimate your full annual bill with the annual bill estimator.
Read our guide: Should I fix my energy tariff before July 2026?
See also: The energy loyalty penalty: why staying costs more
Compare fixed tariffs at your postcode
These projections are illustrative. Use the partner comparison tool to see live fixed and variable tariffs available at your address.