Air Source Heat Pump vs Gas Boiler: 2026 UK Cost Showdown
When a heat pump actually beats a gas boiler in 2026 — with real annual cost numbers for different UK home types.
Air Source Heat Pump vs Gas Boiler: 2026 UK Cost Showdown
Updated: May 2026 — Power Guardian UK Editorial Team
Heat pumps split UK opinion. The truth in 2026 lives in the spreadsheet — your COP, your tariff and your insulation.
The 2026 cost numbers that matter
| Item | 2026 figure | Why it matters | |---|---|---| | Electricity unit rate | 27p/kWh | Drives every kWh the pump uses | | Gas unit rate | 6.5p/kWh | The benchmark to beat | | Typical UK heat demand | 12,000 kWh/yr | Illustrative 3-bed home (Ofgem's current typical gas use is awaiting verified update) | | Heat pump SCOP (real-world) | 3.0–3.5 | Heat out ÷ electricity in | | Gas boiler efficiency | 85% | Modern condensing combi |
Annual running cost by home type
| Home | Heat demand | SCOP | Gas boiler cost | Heat pump (standard) | Heat pump (Cosy tariff) | |---|---|---|---|---|---| | Insulated 2-bed flat | 6,000 kWh | 3.5 | £459 | £463 | £257 | | Average 3-bed semi | 12,000 kWh | 3.2 | £918 | £1,013 | £563 | | Older 4-bed detached | 18,000 kWh | 2.8 | £1,376 | £1,736 | £965 | | Poorly insulated home | 22,000 kWh | 2.5 | £1,683 | £2,376 | £1,320 |
Bottom line: Heat pumps reliably beat gas only with (1) decent insulation, (2) a heat-pump-friendly tariff and (3) a real-world SCOP of 3.0+.
Will the £7,500 BUS grant continue?
Yes — confirmed through 2026. Average install £11–14k, so out-of-pocket is £4–7k.
Should I insulate before installing?
Always. Without insulation upgrades SCOP collapses below 2.8 and running costs match or exceed gas.
Related energy-saving tips
- Consider a heat pump — Air source heat pumps are much more efficient than gas boilers at turning energy into heat, but whether one suits you depends on your home.
- Reduce your combi boiler's flow temperature — Combi boilers run in their more efficient condensing mode when the water they send to radiators is cooler.
- Set heating timers and schedules — Heating an empty home wastes energy. A schedule makes the heating come on when you need it and go off when you don't.