Should you switch from gas to a heat pump? The BUS provides £7,500. But the right answer depends on your home, insulation and electricity tariff. Here is the complete unbiased comparison.
| Factor | Gas boiler | Heat pump |
|---|---|---|
| Upfront cost | around £2,700 for a typical semi (EST, May 2026) | £500–£7,500 (net of BUS) |
| Lifespan | 10–15 years | 15–20 years |
| Running cost (standard tariff) | £850–£1,200/yr | £900–£1,400/yr |
| Running cost (HP tariff) | £850–£1,200/yr | £500–£900/yr |
| BUS grant available | ❌ | ✅ £7,500 |
| Carbon emissions | High | Low & improving |
| Works with existing radiators | ✅ Yes | ⚠ May need upsizing |
Well-insulated home: Best results in homes with EPC C or better — or where insulation improvements are planned alongside installation.
Off-gas-grid property: Oil/LPG homes have the strongest financial case. BUS provides £9,000 (vs standard £7,500) for qualifying off-gas-grid installations until March 2027.
Combining with solar: Solar + heat pump + battery delivers outstanding financial and carbon outcomes. Solar electricity runs the heat pump at near-zero cost.
Poorly insulated home: Install insulation first, then reassess. Heat pumps in poorly insulated homes require larger systems and cost more to run.
Short-term occupancy: If you are unlikely to remain long enough to recover the upfront cost difference, the financial case weakens.
Yes. Gas boilers are not banned for existing properties. Replacing an existing boiler with gas remains legal.
Not for existing properties in the near term. Future homes policy aims to move away from fossil fuel heating in new builds, but no ban on existing-property replacements is in force.
On a specialist heat pump tariff (7–15p/kWh overnight rates), yes — comparable or cheaper. On a standard electricity tariff, gas is typically cheaper per unit of heat. The economics improve as the grid decarbonises.