Heat Pump vs Gas Boiler - Is It Worth Switching in 2026?

Your boiler is on its last legs and you are wondering whether to replace it with another gas boiler or make the switch to a heat pump. Here is an honest breakdown of both options.

Gas Boiler
  • Lower upfront cost (£2,000-4,500)
  • Fast installation (1-2 days)
  • No outdoor unit needed
  • High carbon emissions
  • No government grants available
Heat Pump
  • £7,500 BUS grant available
  • Low carbon - future-proof technology
  • 20-25 year lifespan (vs 10-15 for boiler)
  • Higher upfront cost (£10,000-18,000)
  • Requires outdoor space + hot water cylinder

Full comparison table

AspectGas BoilerHeat Pump
Installation cost£2,000-4,500£10,000-18,000 (£2,500-10,500 after grant)
Running cost (gas)~£800-1,200/yr~£700-1,100/yr (SCOP 3.5+)
Running cost (oil)~£1,400-2,200/yr~£700-1,100/yr
Carbon emissionsHigh (gas: 204g CO2/kWh)Low (grid electricity improving)
Noise levelVery quiet (indoor)38-50 dB (outdoor unit)
Space requiredJust a flueExternal unit + hot water cylinder
Suitability (old homes)ExcellentGood (with insulation)
Lifespan10-15 years20-25 years
Grant availableNoYes - £7,500 BUS
Future-proofingGas ban (new homes from 2025)Technology of the future

Our verdict

For gas boiler users: Running costs are comparable (slight heat pump advantage if SCOP is 3.5+). The £7,500 grant significantly reduces the gap. If you plan to stay in the property 10+ years, a heat pump is increasingly compelling. If the boiler has just broken and you need an emergency replacement, a new boiler may be more practical.

For oil/LPG users: The economics strongly favour heat pumps. Oil and LPG running costs are typically £500-1,000/year higher than a heat pump. Combined with the £7,500 grant, payback periods of 7-12 years are realistic.

Important disclaimer

heatpumpcompared.co.uk is editorially independent and not affiliated with any heat pump manufacturer or installer. We do not provide heating advice. Prices, specifications, SCOP ratings and grant amounts are correct as of April 2026 but are subject to change. Always commission a professional heat loss survey before purchasing a heat pump system.