The October energy price cap will be about £30 lower than analysts predicted three weeks ago. Glazing is standard-rated for VAT at 20%. The zero rate for energy-saving materials covers insulation, heat pumps and solar panels; HMRC names secondary and double glazing as excluded (VAT Notice 708/6). The change, announced by the Chancellor in late July, takes effect on 1 October.
As Solar Power Portal reported, Cornwall Insight’s revision reflects the VAT cut alone, not any structural change in wholesale gas prices, which remain the dominant driver of the cap.
What the VAT cut actually saves a household
Glazing is standard-rated for VAT at 20%. The zero rate for energy-saving materials covers insulation, heat pumps and solar panels; HMRC names secondary and double glazing as excluded (VAT Notice 708/6). Cutting it to zero removes about £25 a year from a typical bill, roughly the cost of a takeaway coffee each month. For a household using 12,000 kWh of gas and 2,900 kWh of electricity, the saving is £21–£24 depending on region. That is not nothing, but it is dwarfed by the £400–£500 increase in the cap since autumn 2021.
Ofgem’s own data shows that the cap peaked at £4,279 in January 2023. Even with the VAT cut, the October 2024 level will be around £1,800, still 60% above pre-crisis levels. The Treasury’s intervention is a political gesture, not a structural fix. The real lever for homeowners remains consumption reduction.
The cap is not a ceiling, it is a floor for efficiency thinking
Every time the cap moves, the media writes it as a headline. But for a homeowner trying to cut costs, the cap is a benchmark, not a target. The typical 3-bed semi on a standard variable tariff will still pay roughly £150 a month from October. That is £1,800 a year that could be redirected into insulation, a heat pump, or solar panels, all of which attract grants through the Boiler Upgrade Scheme and the Great British Insulation Scheme.
The Energy Saving Trust estimates that a well-insulated home with a heat pump can cut heating costs by 20–30% compared with a gas boiler. Solar panels, at current installation costs of £5,000–£7,000, can save £400–£600 a year on electricity. The payback period is 10–12 years, far shorter than the lifetime of the equipment.
Yet the UK still has 19 million homes with EPC ratings of D or below. The VAT cut does nothing to improve that stock. It is a sticking plaster on a haemorrhage.
What the forecast tells us about winter 2024–25
Cornwall Insight’s revision is good news in the sense that the cap is not rising to £1,900 or £2,000 as some feared. But the underlying drivers, gas storage levels in Europe, Russian pipeline flows, and UK wind generation, remain volatile. The consultancy’s senior analyst, Dr Craig Lowrey, noted that the VAT cut “provides some relief, but the cap remains at a level that will cause hardship for many households.”
For homeowners planning upgrades, the message is clear: do not wait for the cap to drop further. It may not. The next quarterly adjustment in January 2025 will reflect winter demand and could push the cap back up. The cheapest energy is the energy you do not use.
Who qualifies, and who doesn’t
The VAT cut applies to all domestic energy bills, regardless of income or tariff type. That means every household gets the £25 saving automatically from October. No application, no means test. But it also means the Treasury forgoes about £1.5 billion in revenue annually, money that could have funded deeper insulation subsidies for low-income homes.
The catch is that the cut is temporary. The government has not confirmed it beyond April 2025. If it reverts, the cap will effectively rise by £25 overnight. Homeowners should treat the saving as a one-off windfall, not a permanent reduction in their baseline costs.
What to do now
Households on standard variable tariffs will see the VAT cut reflected in their October bills automatically. Those on fixed deals, which are now reappearing at rates below the cap, should compare tariffs on Ofgem’s accredited comparison sites. The average fixed deal available today is around £1,720, about £80 below the October cap. Switching could lock in that saving for 12 months.
For the longer term, the VAT cut is a signal to act. The £25 saved annually is less than one month’s saving from a solar array or a properly insulated loft. The Boiler Upgrade Scheme offers £7,500 off a heat pump installation. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. Applications are open now. The cap will rise again. The time to insulate is before winter.
Frequently Asked Questions
Yes, but only by about £2 a month. Glazing is standard-rated for VAT at 20%. The zero rate for energy-saving materials covers insulation, heat pumps and solar panels; HMRC names secondary and double glazing as excluded (VAT Notice 708/6). For a typical dual-fuel household paying £150 a month, the saving is roughly £2.10. You do not need to do anything, your supplier will apply it automatically from October.
It depends on your risk tolerance. Fixed deals are currently around £1,720 a year for a typical household, which is about £80 below the October cap. If you fix now, you lock in that rate for 12 months. But if the cap falls further in January, you may miss out. Compare deals on Ofgem's accredited site and check the exit fees before switching.
