July 2026 energy price cap: Iran war drives forecasts toward £1,929 per household

Ofgem will confirm the July 2026 energy price cap on 27 May, covering the quarter from 1 July to 30 September. On current wholesale market conditions and analyst forecasts, the cap is set to rise by roughly 18% on April's level — adding approximately £288 per year to the typical dual-fuel household bill, on Cornwall Insight's reading.

Today's ONS inflation data confirms why: motor fuel inflation at a three-year high, and domestic heating oil up 95.3% on the year — the highest reading since September 2022. The wholesale pressure feeding those numbers now feeds the July cap calculation.

The forecast range

Forecasts have moved within a narrow range throughout April. Cornwall Insight's current £1,929 figure is a modest fall from its earlier £1,973 prediction, which the firm attributed to 'partial steadying in wholesale markets after a pause in energy infrastructure strikes and signals of a potential ceasefire in the Middle East conflict.' That caveat should be read in both directions — the forecast could fall further on a durable ceasefire, or rise sharply on renewed escalation.

What's driving the rise

The UK imports only about 1% of its gas directly from Qatar per DESNZ's 6 March 2026 factsheet, so the direct exposure to Middle East gas supply is limited. But the UK gas price is set by the global market. Gas still sets the price of electricity in the UK more than 80% of the time. Around 80% of UK households heat with gas. The Strait of Hormuz ships approximately 20% of the world's oil and a significant portion of global LNG; disruption there prices through to UK wholesale within weeks.

The January 2026 cap had been falling on a clear trajectory before the Iran conflict began on 28 February. Pre-conflict forecasts expected the July cap to land lower than the April figure. That path is now gone; today's CPI data with motor fuels at +4.9% year-on-year confirms that the wholesale rise is feeding through to retail prices across the energy complex.

The April fall in context

The April 2026 cap fell by £117 (6.6%) versus January, delivering a typical household saving of about £150 per year. That fall was structural — the government scrapped the Energy Company Obligation (ECO) levy from bills and moved green levies to general taxation. It was not a market-driven fall. The wholesale component of the bill had been broadly stable heading into April.

The July cap will not benefit from a similar one-off structural change. All of the rise that analysts are forecasting is wholesale-driven — which means households should expect the July cap to reflect the cost of gas and electricity supply, rather than a policy lever.

What households can do

Three practical considerations. First, the cap applies only to standard variable tariffs. Households on fixed deals are protected for the duration of the fix. Second, the cheap fixed deals that were available in early 2026 largely disappeared from the market in early March as wholesale prices rose; what remains is priced in line with the new forecasts. Third, the October 2026 cap is currently forecast marginally higher than July, so a short summer-only fix may not be the best value.

For low-income households, the Warm Home Discount and Cold Weather Payment frameworks remain in place. The government has indicated — per the Institute for Government's April 2026 analysis — that additional targeted support may be considered if wholesale prices persist through the October cap window. That is a statement of possibility, not a confirmed policy.

What to watch before 27 May

Three variables will move between now and the Ofgem announcement. One: the duration and intensity of any ceasefire in the Middle East, which sets the wholesale gas trajectory. Two: the April CPI release on 20 May, which will land the week before the cap announcement and confirm whether services inflation is stabilising. Three: the MPC statement following the May meeting, which may indicate whether the Bank views the current inflation trajectory as transitory or entrenched.

For all three, the short-term trajectory is pointing in one direction. A July cap rise is, on current information, the base case.

Frequently asked questions

When will Ofgem confirm the July 2026 price cap?

Ofgem reviews the cap every three months and announces the next level around six weeks before the quarter begins. The July 2026 cap (covering 1 July to 30 September) is due to be confirmed on 27 May 2026. Forecasts between now and then move with wholesale gas prices, which are themselves moving with developments in the Middle East.

How much could the July cap rise?

Cornwall Insight's latest forecast, published earlier this month, is £1,929 per year for a typical dual-fuel household — an 18% rise on the April 2026 cap of £1,641. Independent forecasts from EDF (£1,937), E.ON (£1,955) and MoneyWeek methodology (£1,972) sit in a similar range. These are forecasts, not confirmed figures; the actual cap will be set by Ofgem on 27 May using the wholesale cost window that closes in mid-May.

Why is the cap rising after April's fall?

The April 2026 cap fell by £117 (6.6%) versus the January 2026 level — but that fall was delivered largely by the government scrapping the Energy Company Obligation (ECO) levy and moving green levies to general taxation, saving households roughly £150 per year. Wholesale prices at that time were broadly stable. Since late February, the US-Iran conflict has disrupted energy infrastructure and the Strait of Hormuz, driving wholesale gas prices sharply higher. The July cap will reflect those wholesale rises.

Should I fix my energy tariff now?

This is not financial advice. On the published methodology, Martin Lewis's rule of thumb (24 March 2026) is that any 12-month fix priced up to 11% above the January 2026 cap of £1,758 — approximately £1,952 — is likely to save money over a year on current forecasts. Fixes priced above that threshold are unlikely to save. Always verify against current market offers and your own consumption before deciding.