Is a Heat Pump Cheaper to Run Than Gas in 2026? (UK)
The honest answer for 2026: it depends on your electricity tariff and how well the pump is installed. Because electricity costs more per unit than gas, a heat pump only wins by turning each unit into 3–4 units of heat (its COP). On a standard tariff a good air source heat pump is roughly line-ball with a modern gas boiler; on a dedicated heat pump tariff it usually comes out cheaper to run. A well-designed system is the difference between the two.
Heat pump vs gas running cost — the short answer
- Electricity costs more per unit than gas — so a heat pump only saves money by being far more efficient.
- A good heat pump delivers 3–4 units of heat per unit of electricity (a COP of 3–4); a gas boiler is around 0.9.
- On a standard tariff: running costs are roughly line-ball with gas — sometimes a little more, sometimes a little less.
- On a dedicated heat pump tariff: cheaper off-peak electricity usually makes the heat pump clearly cheaper to run.
- Installation: the £7,500 Boiler Upgrade Scheme grant cuts the upfront cost of a switch.
The single biggest variable is the quality of the installation. A pump sized and commissioned correctly, running at low flow temperatures into well-sized radiators or underfloor heating, achieves a high COP — and that is what tips the running cost in your favour.
Heat Pump vs Gas: Cost Per Unit of Heat (UK 2026)
Illustrative figures based on 2026 price levels. Your own tariff and efficiency will vary the numbers.
The gap between electricity and gas prices (the “spark gap”) is what decides this. As that gap narrows and heat pump tariffs spread, the running-cost case for heat pumps keeps strengthening.
What Makes a Heat Pump Cheaper (or Dearer) to Run
Your electricity tariff
A dedicated heat pump or time-of-use tariff with cheap off-peak rates is the fastest route to beating gas on running cost.
Real-world COP (efficiency)
The higher the seasonal efficiency, the more heat per unit. Low flow temperatures and correctly-sized emitters keep the COP high all winter.
Insulation & heat demand
A well-insulated home needs less heat, so a heat pump runs gently and efficiently. Draughty homes push flow temperatures up and erode savings.
Quality of installation
Correct sizing, commissioning and controls matter more than the brand. A poorly set-up pump can cost more to run than the boiler it replaced.
Common Questions
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