1. What is the price cap and how is it calculated?
The Ofgem price cap is a per-unit ceiling on the price energy suppliers can charge customers on default variable tariffs in Great Britain. Introduced in January 2019, it covers about 85 percent of UK households (those who have not switched to a fixed deal). The cap was designed as a consumer-protection measure after a long-running competition inquiry concluded that millions of households were stuck on overpriced default tariffs without realising they could switch.
What the cap caps: a maximum unit rate for gas (pence per kWh), a maximum unit rate for electricity, and a maximum daily standing charge for each fuel. Together these set the maximum bill structure. The cap is not a total-bill cap. If your usage is high, you pay more. If your usage is low, you pay less. The Ofgem typical household bill figure assumes 11,500 kWh of gas and 2,700 kWh of electricity per year for a dual-fuel direct-debit customer, this is the figure quoted in news headlines.
How the cap is calculated: Ofgem uses a formula that adds together six main components: the wholesale cost of gas and electricity (the biggest single component, typically 35 to 50 percent), network costs (transmission and distribution), policy costs (renewables levies, social schemes), operating costs (supplier admin), a small allowed profit margin, and adjustments for past under- or over-recovery. The wholesale cost is the most volatile piece, which is why the cap moves with energy markets.
The reference period: for each quarter, Ofgem averages wholesale prices over a defined window (typically the three months ending six to eight weeks before the new quarter starts). This averaging is what gives the cap its lag relative to spot markets. If wholesale gas spikes in May, the impact lands in the October cap announcement and bills from October onwards. This is also why a sudden de-escalation in wholesale markets does not give immediate relief to bill payers.
What is NOT capped: fixed-rate tariffs are outside the cap. Suppliers can price fixed deals above or below the current cap level. Prepayment meter tariffs have a separate cap. Northern Ireland has a different regulatory regime. Business customers are outside the domestic cap. For a deeper explanation of how price moves transmit from Brent crude through gas and into electricity bills, see our glossary entry on the pass-through effect.
2. Quarterly breakdown 2026 (Q1 to Q4)
Below is the quarterly review schedule for 2026, with announcement dates and the period each cap covers. For specific cap values, always consult the latest Ofgem announcement at ofgem.gov.uk, the figures change with every quarterly review and any numbers we cite here are time-stamped as of May 2026.
| Quarter | Cap period | Announcement |
|---|---|---|
| Q1 2026 | 1 January to 31 March 2026 | Late November 2025 |
| Q2 2026 | 1 April to 30 June 2026 | Late February 2026 |
| Q3 2026 | 1 July to 30 September 2026 | Late May 2026 |
| Q4 2026 | 1 October to 31 December 2026 | Late August 2026 |
Why quarters matter: the seasonal pattern of UK energy demand is heavily winter-skewed. Roughly 60 to 65 percent of an average household's annual energy use happens in Q1 (January to March) and Q4 (October to December). This means the autumn cap announcement (late August, for the October-to-December cap) is the single most consequential of the year, because it sets the rate for the period of highest consumption. A bad Q4 cap is felt more acutely than a bad Q2 cap.
The forecast cycle: Cornwall Insight and other analysts typically publish a rolling four-quarter forecast that gets refined as each Ofgem announcement window approaches. The further out a forecast goes, the more uncertainty it carries, because wholesale gas markets are sensitive to weather, geopolitics, and storage levels. A forecast made in March for the October cap is a useful indicator of direction but not a precise number.
Historical context: the cap was relatively stable for the first three years after introduction, rising sharply in 2022 to 2023 with the European energy crisis. Since 2024 the cap has settled back into a higher-than-pre-2022 baseline but with quarterly oscillations of 5 to 15 percent. Households should expect normal quarterly variation to be in the £100 to £200 range up or down on the typical-bill figure, with larger moves reserved for crisis periods.
What would the next Brent shock add to your bill?
The wholesale gas market that drives the cap moves with Brent. Run the 60-second calculator to see how a 10 or 20 dollar spike could change your annual costs.
Run the 60-second calculator3. Cornwall Insight 12-month forecast
Cornwall Insight is the UK's most-cited independent energy-market analyst. Their rolling 12-month price-cap forecast is published several times a quarter and is the figure that drives most national news headlines about future energy bills. Other forecasters exist (EnAppSys, ICIS, Bloomberg NEF, Aurora Energy Research), but Cornwall is the public-facing benchmark.
How Cornwall's forecast works: they take current wholesale market data (NBP gas futures, day-ahead and forward electricity prices, EU TTF gas as a sentiment indicator), apply the Ofgem cap methodology to project what each component of the cap formula would look like at the next announcement window, and add commentary on the policy and regulatory side. The forecast is updated frequently as new wholesale market data arrives, so the headline number you see in any given week can change by the next.
Anti-Fantasy note: we deliberately do not publish our own forecast on this page. Forecasting wholesale energy prices is a specialist activity, the model uncertainty is high, and our value-add is not in beating Cornwall Insight at their own game. We instead point readers to the original source, treat Cornwall's figures as well-informed estimates, and focus our methodology on how households can interpret and act on these forecasts rather than on producing competing numbers.
Where to read the latest:
- cornwall-insight.com, original press releases and blog posts
- BBC Business, secondary coverage of Cornwall announcements
- MoneySavingExpert utilities, accessible summaries with practical advice
One practical heuristic: if Cornwall's forecast for the next quarter changes by less than 5 percent in either direction relative to the current cap, treat the change as routine quarterly noise. Changes above 10 percent in either direction usually indicate a meaningful wholesale-market move and are worth planning around (whether by switching to a fixed tariff if a rise is forecast, or by holding off on switching if a fall is forecast).
4. Standing charges debate
The standing charge is the daily flat fee you pay regardless of how much energy you use. In 2026 it has become a contested political issue, with some advocacy groups arguing that the structure penalises low-use households (typically pensioners, single-person homes, or well-insulated properties) who pay disproportionately more per unit of energy than they would on a usage-only billing model.
What standing charges cover: network costs (maintaining gas and electricity infrastructure), policy costs (the renewables levies and social-tariff schemes), supplier operating costs that are fixed per customer rather than per unit, and a small recovery component for the cost of historic supplier failures during the 2021 to 2023 supplier-failure wave.
Why the debate matters: standing charges in 2025 to 2026 are at historic highs in the UK, partly because of the costs absorbed from failed suppliers in the energy crisis. A typical dual-fuel household pays around £300 per year in standing charges alone, before consuming a single kWh. For a low-use household using only 4,000 kWh of gas a year (rather than the 11,500 kWh typical figure), the standing charge can be a third of the total bill. Critics argue this is regressive, defenders point to network costs being genuinely fixed per connection.
Ofgem review: Ofgem has been running a structured review of standing charges since 2024, with stakeholder consultations and proposals to consider zero-standing-charge tariff options as a regulatory floor. As of May 2026 no binding decision has been published, but the direction of travel suggests that suppliers will be required to offer at least one low-or-no-standing-charge tariff option by the end of 2026 or early 2027. The detail will matter, because shifting more cost onto the unit rate could disadvantage high-use households even as it helps low-use ones.
Practical implication: if you are a low-use household, watch for the Ofgem decision and consider switching to a low-standing-charge tariff once they appear. If you are a high-use household, the standing-charge debate is less critical for your bill, but the unit-rate side of the equation is, and that depends mostly on the cap level and your insulation status.
5. How to reduce your dependency on the cap
The cap moves with wholesale markets, which means your bill exposure follows the wholesale gas price. Three structural moves reduce your dependency on the cap over time, and a fourth helps you ride out short-term spikes.
Move 1: Insulation top-up
Loft insulation and cavity-wall insulation are typically the highest-return measures available, with payback in 3 to 8 years against current gas prices. If your EPC flags either as a recommendation, this is usually the first move, and ECO4 may pay for it if you are eligible.
Move 2: Heat pump installation (BUS-funded)
The Boiler Upgrade Scheme grant of £7,500 dramatically improves heat pump economics. Once installed, you shift your heating demand from gas to electricity, where you can also access time-of-use tariffs that further cut running costs. See our BUS calculator sub-page for the cost breakdown.
Move 3: Solar plus battery
Domestic solar with a battery means a substantial chunk of your electricity is no longer billed at the cap rate, and you can use a smart-export tariff to earn back from exporting surplus. Costs have come down significantly since 2022. The Smart Export Guarantee (SEG) replaced the old Feed-in Tariff but pays meaningful rates with the right supplier.
Move 4: Switch to a smart tariff or fixed deal
If a Cornwall forecast suggests the next cap announcement will lift rates by 10 percent or more, locking in a fixed tariff before the announcement can be valuable. Conversely, if the forecast is for a fall, the cap (variable rate) will often track that fall faster than fixed tariffs can re-price downward. Tools like the MoneySavingExpert Cheap Energy Club aggregate the available switches.
None of these moves eliminate cap exposure entirely (you will always have some bill), but together they can reduce your annualised energy spend by 30 to 60 percent over a 5 to 10 year horizon. The economics are clearly better than they were three years ago, mainly because of the BUS grant and the Smart Export Guarantee. For more on the underlying oil shock dynamics that drive wholesale gas, see our glossary.
Plan around the next cap announcement
Whatever Cornwall forecasts, your household impact depends on usage. Calculate your specific scenario in 60 seconds.
Open the household calculator