Wiso Savings · Updated 3 November 2026
Fixed or variable energy tariffs?
Understand what is fixed, what can change and what to check.
Fixed rates do not mean a fixed bill
A fixed tariff sets agreed energy rates for a specified period. The total you pay still depends on how much you use, and your monthly payment may change to reflect usage or your balance. Read the contract for the treatment of tax changes and other exceptions.
Variable rates can move
Variable tariffs can change their unit rates and standing charges. A fixed tariff offers rate certainty, while a variable tariff can benefit if its rates fall. Neither is automatically cheaper. Compare the current offer, its duration and the consequences if rates move in either direction.
Check the cost of leaving
Some fixed-term products have exit fees, potentially for each fuel. Check both your existing contract and the proposed one. A small advertised saving can disappear once leaving costs or bundled services are included. Do not rely on a headline monthly payment alone.
Choose for your circumstances
Think about your budget, plans to move, meter type and when you use energy. Ask the supplier to explain anything unclear in writing. Wiso does not forecast future prices or recommend a tariff for your personal circumstances.
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Written by Wiso Savings. General information for households in Great Britain; check your supplier’s current terms.
Ofgem: energy terms explained · Citizens Advice: choosing a tariff (England)
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