Air source heat pump vs Gas boiler
Side-by-side comparison, when-to-use-each guide, and instant conversion. Reviewed for 2026.
New builds, well-insulated homes, off-grid properties, homes eligible for the £7,500 Boiler Upgrade Scheme.
Existing poorly-insulated homes, quick boiler replacement, where gas network access and prices remain favourable.
| Aspect | Air source heat pump | Gas boiler |
|---|---|---|
| Energy source | Electricity (200-400% efficient) | Gas (90% efficient) |
| UK running cost | Depends on COP and electricity rate | Typically cheaper at 2026 energy prices |
| Installation cost | £8,000-15,000 | £2,000-3,500 |
| Grant available | £7,500 Boiler Upgrade Scheme | None |
| Carbon output | Low (with green electricity) | Higher (burning fossil fuel) |
Frequently asked
Is a heat pump worth it in 2026?
For new builds and well-insulated homes with the £7,500 grant: often yes. For typical older semi-detached houses without good insulation: the COP drops and running costs may not beat gas. Get a professional heat loss calculation before committing.
What COP does a heat pump need to beat gas?
With electricity at 24p/kWh and gas at 7p/kWh, you need COP above 24/7 = 3.43 to beat gas on running costs. Modern heat pumps achieve COP 2.5-4 depending on outside temperature — they're less efficient in cold weather.