The big question: Heat pump or gas boiler in 2026?
With energy prices remaining high and the UK government pushing towards net zero, the choice between a heat pump and a gas boiler has never been more consequential for homeowners. Whether your current boiler is failing or you're planning ahead, this guide gives you the real numbers.
The short answer: for most well-insulated UK homes in 2026, a heat pump will save you money over its lifetime — especially with the £7,500 Boiler Upgrade Scheme (BUS) grant. But the full picture depends on your home's insulation, your radiator setup, and your willingness to invest upfront.
Bottom line: At 2026 energy prices (electricity at 24.5p/kWh, gas at 6.4p/kWh), a heat pump with a COP of 3.5 delivers heat at an effective cost of 7.0p/kWh — comparable to a 90% efficient gas boiler at 7.1p/kWh. Factor in the £7,500 BUS grant, and a heat pump wins on total cost of ownership.
Running cost comparison: 2026 energy prices
Let's look at the actual numbers for a typical 3-bedroom semi-detached house using 12,000 kWh of heat demand per year (the UK average):
| Cost Factor | Air Source Heat Pump | Gas Boiler (A-rated) |
|---|---|---|
| Fuel price (2026) | 24.5p/kWh electricity | 6.4p/kWh gas |
| Efficiency | COP 3.5 (350%) | 92% efficient |
| Effective heat cost | 7.0p/kWh | 7.0p/kWh |
| Annual heating cost | £840 | £835 |
| Hot water cost | £190 | £210 |
| Annual service cost | £100-£150 | £80-£120 |
| Total annual cost | £1,130-£1,180 | £1,125-£1,165 |
At current prices, the running costs are remarkably similar. However, two key trends favour heat pumps going forward:
- Gas prices are expected to rise — the UK's gas supply is increasingly imported and subject to global volatility
- Electricity prices are falling — as more renewable energy comes online, wholesale electricity costs decline
- Carbon taxes on gas — the government is considering rebalancing energy levies to make electricity cheaper relative to gas
- Heat pump efficiency improves — well-maintained systems in insulated homes often achieve COP 4.0+, making them even cheaper
Installation costs: The upfront investment
This is where the difference is most obvious. Heat pumps cost significantly more to install, but grants dramatically close the gap:
| Installation Factor | Air Source Heat Pump | Gas Boiler Replacement |
|---|---|---|
| Equipment + installation | £10,000-£15,000 | £2,500-£4,500 |
| BUS grant available | -£7,500 | None |
| Your cost after grant | £2,500-£7,500 | £2,500-£4,500 |
| Radiator upgrades (if needed) | £1,000-£3,000 | Not usually needed |
| Equipment lifespan | 20-25 years | 12-15 years |
| Cost per year of ownership | £125-£375 | £167-£375 |
After the £7,500 BUS grant, the installation cost of an air source heat pump is comparable to a premium gas boiler. And because heat pumps last nearly twice as long, the annualised cost of ownership is often lower.
Some households can also get completely free heat pump installations through the ECO4 scheme if they receive qualifying benefits. Check your eligibility to see which grants you can access.
Environmental comparison
If reducing your carbon footprint matters to you, the comparison is clear:
| Environmental Factor | Heat Pump | Gas Boiler |
|---|---|---|
| CO₂ per year (heating) | 0.7 tonnes | 2.5 tonnes |
| Fossil fuel use | None (electric) | Direct gas combustion |
| Improves with grid | Yes — gets greener over time | No — locked to gas |
| Air quality impact | Zero local emissions | NOx and CO₂ from flue |
| Lifetime CO₂ (20 yrs) | ~14 tonnes | ~50 tonnes |
A heat pump produces roughly 70% fewer carbon emissions than a gas boiler. As the UK electricity grid continues to decarbonise (it's already over 50% renewable), heat pumps become even greener over time. A gas boiler's emissions remain constant throughout its life.
Heat pump pros and cons
✓ Heat Pump Advantages
- Lower running costs in well-insulated homes
- £7,500 government grant available (BUS)
- 20-25 year lifespan (vs 12-15 for boilers)
- 70% lower carbon emissions
- Provides cooling in summer
- No gas supply needed
- Less annual maintenance required
- Future-proof as gas is phased out
✗ Heat Pump Drawbacks
- Higher upfront cost (even after grant)
- Needs well-insulated home for best results
- May need larger radiators or underfloor heating
- Outdoor unit takes garden space
- Some noise from outdoor unit
- Lower flow temperature than gas boilers
- Needs qualified MCS-certified installer
- Installation takes 2-3 days (vs 1 for boiler)
Gas boiler pros and cons
✓ Gas Boiler Advantages
- Lower upfront cost (£2,500-£4,500)
- Works with existing radiators and pipework
- Familiar technology — easy to find engineers
- Quick installation (typically 1 day)
- High flow temperature for quick warm-up
- Compact size — fits in a kitchen cupboard
- No external unit required
- Established supply chain and parts
✗ Gas Boiler Drawbacks
- Rising gas prices increase running costs
- Shorter lifespan (12-15 years)
- Annual gas safety check legally required
- Carbon emissions (2.5 tonnes CO₂/year)
- Dependent on volatile gas market
- No government grants for replacement
- Future phase-out expected
- Air quality impact from combustion
Which is better for your home?
The right choice depends on your specific situation. Here's a quick decision guide:
Choose a heat pump if:
- Your home is well-insulated (or you plan to insulate first)
- You have outdoor space for the unit (about 1m × 1m)
- You can access the £7,500 BUS grant or ECO4 funding
- You plan to stay in your home for 10+ years
- You want to reduce your carbon footprint
- You'd consider underfloor heating or larger radiators
Stick with a gas boiler if:
- Your home has poor insulation and you can't improve it (e.g., listed building)
- You need a quick, low-cost replacement and your boiler has died
- You're planning to move within the next few years
- Your property can't accommodate an outdoor unit
How to get a heat pump with the BUS grant
The Boiler Upgrade Scheme provides a £7,500 voucher towards the cost of an air source or ground source heat pump. Here's how to claim it:
- Check eligibility — you must own the property and have a valid EPC (use our eligibility checker)
- Get quotes from MCS-certified installers — they handle the grant application for you
- Installer applies for the voucher — approved within days in most cases
- Installation completed — typically takes 2-3 days
- Grant paid directly to installer — you only pay the difference
Can you get a free heat pump? If you receive qualifying benefits, you may be eligible for a completely free heat pump through the ECO4 scheme, or you can combine ECO4 with BUS. Enter your postcode to check what you qualify for.
The 20-year total cost comparison
Looking at the complete picture over 20 years (the typical heat pump lifespan), including replacement of a gas boiler at year 13:
| 20-Year Costs | Heat Pump | Gas Boiler |
|---|---|---|
| Installation (after grants) | £5,000 | £3,500 |
| Running costs (20 yrs) | £20,600 | £22,500 |
| Maintenance (20 yrs) | £2,500 | £2,000 |
| Replacement at year 13 | None needed | £4,000 |
| Total 20-year cost | £28,100 | £32,000 |
| 20-year saving | £3,900 cheaper with heat pump | |
Over 20 years, a heat pump saves approximately £3,900 compared to gas — and this estimate is conservative. If gas prices rise faster than expected (which most analysts predict), savings could be substantially higher. Plus, you'll have produced 36 fewer tonnes of CO₂.