On 20 September 2023 the Prime Minister, Rishi Sunak, announced changes to net zero policy, including that "the phase out date for installing new oil and LPG boilers and new coal heating for off-grid homes would be put back to 2035"1. The previous date for off-grid homes had been 20262. The same announcement raised Boiler Upgrade Scheme grant values for air source and ground and water source heat pumps to £7,500 per installation, with biomass boiler grants remaining at £5,000, effective from Monday 23 October 20233.
The Heat Pump Association, responding the following day, said the 2035 date was seven years later than the Committee on Climate Change recommended for off-gas-grid homes and two years later for gas2. It also noted that the £7,500 figure represents a 50 per cent uplift for air source heat pumps but only a 25 per cent increase on the previous £6,000 grant for ground source units2. The association said the scheme's budget would support 20,000 heat pumps a year, which it described as 3 per cent of the 600,000 annual installations targeted for 20282.
"The Government has once again moved the goalposts for heat decarbonisation in the UK, and this risks damaging investor, installer and consumer confidence in this space unless this re-confirmed end date for fossil fuel boilers is strengthened from being an 'ambition' to being a firm commitment."
The government also set an exemption to the 2035 phase-out for households expected to struggle most to switch, which it estimated would cover about a fifth of homes, including off-gas-grid properties2. The Heat Pump Association said no evidence had been published to support that one-fifth figure2. MCS, the certification body, said the delay was disappointing and that "moving the goalposts now risks confusing home and business owners about what the right thing to do is"3.
Households already holding a live Boiler Upgrade Scheme voucher keep the original value: £5,000 for air source heat pumps or biomass boilers and £6,000 for ground and water source heat pumps. Vouchers can be revoked and re-applied for at the higher value once the changes take effect, but anyone who has already received a grant is not eligible for an uplift3.
Why it matters for households
For a home off the gas grid, the 2035 date means a replacement oil, LPG or coal heating system can still be installed for roughly another decade, rather than from 2026. Off-grid homes are more likely than others to be in fuel poverty, partly because they tend to be less energy efficient1. Heating oil prices are not regulated in the way gas and electricity prices are, so they can vary day to day and between local areas far more widely1. At March 2026 prices, mains gas was estimated to be the cheapest way to heat a standard three-bed semi-detached house, followed by heating oil, then LPG, though the estimates do not account for off-grid properties typically being larger and less efficient1. The grant uplift changes the upfront cost of a heat pump, not the running cost, and the Heat Pump Association has argued that electricity prices relative to fossil fuels need to fall for heat pumps to be competitive on bills2.
What happens next
The grant changes took effect on 23 October 20233. The Heat Pump Association called for the 2035 end date to be made a firm commitment, for the Future Homes and Buildings Standards to be introduced in 2025 for new build, for the Boiler Upgrade Scheme budget to be increased, and for action to reduce electricity prices relative to fossil fuels2. The government has not published the detailed criteria for the exemption covering about a fifth of homes2.
Sources3 cited
- [](https://researchbriefings.files.parliament.uk/documents/CBP-9838/CBP-9838.pdf), researchbriefings.files.parliament.uk
- HPA urges Government to firm up commitment to phasing out fossil fuel boilers - HPA UK, hpauk.org.uk
- Prime Minister announces Boiler Upgrade Scheme grant increase to £7,500 - MCS, mcscertified.com