Gas Boiler vs Heat Pump
The Full 2026 Cost Comparison
A gas boiler costs less upfront. A heat pump costs less over 15 years. Here is the honest maths for a typical UK home.
Updated April 2026
Head-to-Head Comparison
| Factor | Gas Boiler | Air Source Heat Pump | Ground Source Heat Pump |
|---|---|---|---|
| Install cost | £2,000 - £3,500 | £8,000 - £15,000 | £15,000 - £35,000 |
| BUS grant | None | £7,500 | £7,500 |
| Net install cost | £2,000 - £3,500 | £500 - £7,500 | £7,500 - £27,500 |
| Annual running cost | £780 - £950 | £550 - £850 | £400 - £700 |
| Annual service cost | £80 - £120 | £100 - £200 | £100 - £150 |
| Lifespan | 12 - 15 years | 20 - 25 years | 20 - 25+ years |
| 10-year TCO | ~£11,600 | ~£12,000 | ~£18,500 |
| 15-year TCO | ~£16,100* | ~£15,250 | ~£22,000 |
*Gas boiler TCO at 15 years includes a replacement boiler at year 12-15 (add ~£2,500). Heat pump keeps running. All figures for a 3-bed semi at Q2 2026 energy prices.
10-Year Total Cost of Ownership
Gas Boiler
Air Source Heat Pump
At 10 years, gas wins by roughly £800. The lower upfront cost of a gas boiler still outweighs the running cost savings of a heat pump at current energy prices. The gap is narrower than many people expect, thanks to the £7,500 BUS grant.
15-Year Total Cost of Ownership
This is where the comparison shifts. A gas boiler typically needs replacing after 12-15 years, adding another £2,500 to the total. A heat pump keeps running for 20-25 years.
Gas boiler (15 years)
£16,600
Includes replacement boiler at year 13
Heat pump (15 years)
£15,750
No replacement needed, still has 5-10 years left
At 15 years, the heat pump pulls ahead by roughly £850. And it still has another 5-10 years of life remaining, while the gas boiler is on its second unit. This crossover point is the key decision factor for homeowners planning long term.
Boiler Upgrade Scheme (BUS) Grant
Air source heat pump
£7,500
Ground source heat pump
£7,500
Air-to-air (from April 2026)
£2,500
The grant is applied directly by the MCS-certified installer, so you never pay the full price. You must have a valid EPC (Energy Performance Certificate) and the property must not be a new build. The installer handles the application.
For full details on all grants and finance options, see our grants and finance guide.
Property Suitability Checklist
A heat pump suits your home if...
- Your home has good insulation (EPC C or above)
- You have space for an outdoor unit (side of house or garden)
- You have underfloor heating or oversized radiators
- You are doing a major renovation anyway
- You plan to stay in the property for 10+ years
- Your property is semi-detached, detached, or end-terrace
Stick with gas if...
- Your home has poor insulation (EPC D, E, or below)
- You have no space for an outdoor unit
- You have standard-size radiators throughout
- You live in a mid-terrace or flat
- Your boiler has broken down and you need heat now
- You plan to move within 5 years
Hybrid Heating Systems
A hybrid system combines a small air source heat pump with a gas boiler. The heat pump handles heating in milder weather (roughly 80% of the year), while the gas boiler kicks in during cold snaps when the heat pump would struggle.
Install cost
£4,000 - £8,000
Annual running cost
£600 - £800
Best for
Homes not ready for full heat pump
Hybrids are growing in popularity in 2026. They work well in homes with standard radiators and average insulation where a full heat pump would not perform efficiently. They are a practical stepping stone.
What About Hydrogen?
Hydrogen-ready boilers can switch from natural gas to hydrogen if the gas network converts. Most major boiler manufacturers now sell hydrogen-ready models at no or minimal price premium (£0-200 extra). The government decision on whether hydrogen will be used for home heating was expected in 2026.
Our advice: a hydrogen-ready boiler has no downside (same price, same performance on gas), but do not buy one expecting hydrogen to arrive soon. The infrastructure for hydrogen heating does not yet exist and may never be deployed at scale. For more on the policy landscape, see our 2035 gas boiler ban explainer.
Frequently Asked Questions
Is a heat pump cheaper to run than gas?
At Q2 2026 energy prices, an efficient heat pump (COP 3.5+) in a well-insulated home costs roughly £550-700 per year to run, compared with £780-950 for a gas boiler. The savings are around £100-250 per year. In a poorly insulated home, the heat pump may cost more to run than gas.
How much does a heat pump cost after the grant?
An air source heat pump costs £8,000 to £15,000 before the grant. After the £7,500 BUS grant, you pay £500 to £7,500. The average homeowner pays around £4,000 to £5,000 after the grant for a standard installation.
Can I keep my radiators with a heat pump?
Heat pumps run at lower water temperatures than gas boilers. If your radiators are already oversized for the room or you have underfloor heating, they will work fine. If your radiators are small and standard-sized, you may need to upgrade some or all of them to larger models, adding £1,500 to £3,000.
What is a hybrid heating system?
A hybrid system combines a small air source heat pump with a gas boiler. The heat pump does most of the work in mild weather, and the gas boiler handles cold snaps. It costs £4,000 to £8,000 to install and is ideal for homes that are not ready for a full heat pump conversion.