The government wants heat pumps in every home eventually. Gas boilers are still being installed in millions of UK homes. Here's how to make the right choice for your situation in 2025.
Upfront cost
Combi boiler: £1,400–£2,200 installed. Air source heat pump: £8,000–£15,000 installed (before the £7,500 BUS grant). After the grant, a heat pump can cost £2,000–£7,500 — comparable to a premium boiler installation.
Running costs
With gas at approximately 7p/kWh and electricity at 28p/kWh: a gas boiler at 94% efficiency costs about 7.4p per kWh of heat. A heat pump at COP 3.0 costs about 9.3p per kWh of heat. Gas currently wins on running cost for most UK homes.
Carbon emissions
The UK grid is increasingly renewable. A heat pump at COP 2.5 produces fewer carbon emissions than a gas boiler today — and this advantage grows as the grid decarbonises.
Suitability
Heat pumps work best in well-insulated homes (EPC C or better) with larger radiators or underfloor heating. Gas boilers work in almost any property.
Future-proofing
The gas boiler ban on new builds is in place. For existing homes, no forced replacement deadline exists currently. A new gas boiler bought in 2025 will likely last into the 2040s.
Our honest verdict
Good insulation and no urgency: consider a heat pump and the BUS grant. Older home, tight budget, urgent replacement: gas combi remains the practical choice. We install both and will give you an honest recommendation. Book a free survey.