Homes rated Energy Performance Certificate band F could see average annual dual fuel bills of around £2,340 under Ofgem's price cap from April, according to analysis published by the Energy and Climate Intelligence Unit (ECIU) on 25 March 20251. That is around £700 more than the figure for an EPC band C home, which the ECIU describes as the Government's target1.
The ECIU analysis applies prices under Ofgem's price cap for Q2 2025 to a full year's demand at Typical Domestic Consumption Values, and to median demand at different EPC bands drawn from the DESNZ National Energy Efficiency Database1. The ECIU states the Q2 prices are illustrative of costs for the year, on the assumption that prices do not vary much across the other three price caps over the coming 12 months1.
The gap narrows for better-rated homes. Those in EPC band D properties, which the ECIU calls the UK's most common rating, could see bills around £250 higher than those in band C1. The analysis also notes two anomalies in the figures: EPC band G homes show lower energy bills than band F, and band A slightly higher than band B, which the ECIU attributes to the way the EPC is calculated, with band G homes often using secondary heat sources such as biomass and band A homes able to use electricity1.
| EPC band | Indicative annual dual fuel bill under the Q2 2025 price cap |
|---|---|
| Band F | Around £2,340 |
| Band D | Around £250 more than band C |
| Band C | Government target; around £700 less than band F |
The ECIU points to tenure as a dividing line. It says 1 in 2 homes (52%) in the private rented sector fall below the Government's target of EPC band C, compared with less than a third (28%) of socially rented homes1. On insulation, around 60% of private rented properties with cavity walls have insulation, against around 80% in the social rented sector; for solid walled properties the figures are less than 10% and around 25% respectively1.
Government data cited in the analysis shows private renters receiving housing support are more likely to live in the least efficient homes: around two-thirds (65%) live in properties rated band D or below, compared with around half (49%) of those not receiving housing support1. Around 1 in 7 (15%) private renters receiving housing support report a damp problem, against 8% of those not receiving it and 6% of social renters receiving housing support1. A quarter (25%) of those receiving housing support said they could not keep their home warm, compared with 16% of those not receiving it1.
"The last government promised to introduce and then delayed new minimum standards for landlords so that properties didn't cost the earth to heat, and this government has pushed them back again to 2030."
Ralston added that private landlords could have been required to invest up to a few thousand pounds in insulating their properties, and that the lack of investment leaves many households in more need of financial support and the UK more dependent on gas imports as heat from boilers leaks out of homes1.
Why it matters for households
The figures set out the running cost attached to a home's energy performance, not to the tariff a household picks. Two homes on the same price cap rates can face bills hundreds of pounds apart because of the fabric of the building, and the gap between band F and band C is the largest in the analysis. For a household, that difference is money spent on heat that does not stay in the home, and it reduces the benefit of any switch to a cheaper supplier or a fixed deal. It also bears on energy independence at the household level: a leaky home needs more gas, and the ECIU links that demand to the UK's reliance on gas imports1. The analysis places private renters, and particularly those receiving housing support, in the least efficient and most expensive to heat properties, a group with limited scope to commission insulation work themselves1.
What happens next
The ECIU states that minimum standards for landlords have been pushed back to 20301. No further timetable for those standards is given in the analysis. The bill figures rest on Q2 2025 price cap prices applied across a full year, and the ECIU notes that later price caps could differ1.