The energy price cap for 1 January to 31 March 2027 is now forecast to rise by around 23%. The three supplier forecasts published this week put it at £2,098 to £2,135 a year for a typical dual-fuel household paying by Direct Debit, against £1,723 from 1 October. That is roughly £395 a year more, or about £33 a month, arriving in the quarter when homes use the most energy.
What Martin Lewis said on 24 September
Predictions have “dropped a little, from up 25% last week it's now ‘only’ up 23%”. With five of the thirteen assessment weeks gone, he says it is “almost certainly” going to be a big rise, “likely between 15% and 30% depending on the mid east”. His advice if you're on the cap: consider getting off it by comparing and finding the cheapest fix.
The latest forecasts
Supplier forecasts as collated by MoneySavingExpert in the week of 21 September 2026. All figures use Ofgem's current typical household of 2,500 kWh electricity and 9,500 kWh gas a year, so they compare directly with October's £1,723.
What it could mean for your bill
The cap limits unit rates and standing charges, not your total bill, but a percentage rise in the cap lands on most bills at roughly the same percentage. Here's the extra cost at an annual rate, depending on what you pay now:
For your own usage, the savings calculator applies the January forecast to your bill and puts it next to today's fixed rate.
Why the forecast jumped
In August, Cornwall Insight forecast a January cap of about £1,872, a rise of under 9%. That was calculated from wholesale prices on 25 August. Since then, the conflict in the Middle East has pushed up wholesale gas, which drives both gas and electricity prices. On 24 September, gas for delivery this winter was trading around 181p a therm.
Ofgem sets the January cap from wholesale prices over a window that runs from mid-August to mid-November. Five of those thirteen weeks have passed, so what happens to gas over the next eight weeks still matters a great deal. That is why Martin Lewis gives such a wide range. Ofgem will confirm the real figure in late November, and it takes effect on 1 January.
Nothing new softens it. Electricity VAT is already at 0% in October's £1,723 and stays there until 31 March, so it gives no further relief in January. If you receive means-tested benefits, the £150 Warm Home Discount is paid between November and March.
Should you fix now?
Martin Lewis's advice is to compare the whole market and find the cheapest fix. For reference, Octopus's 12M Fixed currently averages about £1,817 a year nationally for a typical household. That's around £94 more than October's cap, but around £300 less than January's forecast. Its 18-month fix is cheaper still, at about £1,738.
Two things to weigh before you fix:
- Fixed prices move with the wholesale market too. If January's forecast keeps rising, new fixes will get more expensive. Waiting for certainty has a cost.
- Exit fees are the price of changing your mind. If the Middle East calms down and wholesale prices fall back, the rise could land near the bottom of the range, and a fix taken now could end up costing more than the cap. Octopus charges £50 per fuel to leave its 12-month fix early (£75 on the 18-month), against £25–£150 per fuel elsewhere. No supplier can charge one in the last 49 days of a fix.
If you'd rather not decide today, you can switch to Flexible Octopus now. It follows the cap, has no exit fee, and lets you pick up the £50 referral credit and then choose whether to fix once you can see your own quote. Our guide to fixing or staying variable works through the decision in more detail.
We track every new forecast on our price cap predictions page and will report Ofgem's confirmed January figure here the day it's announced.
Sources: MoneySavingExpert — price cap predictions, Cornwall Insight, Catalyst Commercial — wholesale gas prices, Octopus Energy product data and Ofgem. Figures last checked 25 September 2026.
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