Add the deal you're offered and what you pay now.
Your variable rates now
The fixed deal
£93.88 less over 12 months
On 2,500 kWh a year, the variable rates cost £858.13 over the term and the fixed deal £764.25.
A fixed deal locks both figures for the term; a variable tariff follows Ofgem's cap, which is revised every three months. Check the exit fee and the end date on the supplier's own page before you sign.
What the calculator assumes
It works out a year's cost for each set of rates — your usage at the unit rate, plus the standing charge for every day — then takes the share of that year covered by the fixed term. So an 18-month term is charged a year and a half of both figures. It does not forecast wholesale prices or guess where the cap will go next quarter; it only compares the numbers you put in.
The exit fee is part of the deal
Most fixed tariffs charge you for leaving before the term ends, and some charge a fee for each fuel. Where a fixed deal is only a few pounds cheaper than your variable rates, an exit fee of £30, £50 or £60 a fuel can wipe out the saving completely if your circumstances change. Enter the exit fee here so you see the real figure, and check the exact amount and the end date on the supplier's own terms before you sign.
When fixing is worth it
Fixing buys certainty rather than a guaranteed saving. If your budget cannot absorb a winter rise, paying a little more now for a price you know may be the better trade. If the fixed deal is dearer than your variable rates and the cap has been falling, waiting costs you nothing but the chance to switch later. Either way, the variable figures you use here should be the ones on your own bill, and the fixed figures the ones on the supplier's written quote.
The starting rates are Ofgem's price cap averages for 1 October to 31 December 2026 for a default tariff paid by Direct Debit in England, Scotland and Wales, and the starting usage figures are Ofgem's medium-consumption averages. Ofgem's cap is a maximum per unit, not the price you are promised: your supplier sets your rates, they differ by region and meter type, and prepayment customers pay different rates again. Check the unit rate and standing charge on your own bill before you act on anything here.
Next steps
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