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 a unit of electricity costs roughly four times as much as a unit of 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.
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Heat pump vs gas running cost — the short answer
- Electricity costs more per unit than gas — around four times more — 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 — you can check the latest unit rates against the Ofgem price cap. 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.
When a Heat Pump Wins — and When Gas Still Wins
There is no single answer for every home. The running-cost result turns on a handful of things you can actually check before you commit.
A heat pump usually wins when…
You are on (or can move to) a dedicated heat pump tariff, the home is reasonably insulated, and the system is sized to run at low flow temperatures with a real-world COP above 3.5. In that setup the efficiency easily overcomes the price gap between electricity and gas.
Gas can still win when…
You stay on a standard single-rate electricity tariff, the property is draughty or hard to insulate, or the pump is oversized and runs at high flow temperatures. A poorly commissioned system can drift below a COP of 3 and cost more to run than the boiler it replaced.
Illustrative example (not a quote): take a home needing about 12,000kWh of heat a year. A 92%-efficient gas boiler burns roughly 13,000kWh of gas; the fuel is cheap per unit, which is exactly why it is hard to beat. The same heat from a pump running at a COP of 3.4 needs about 3,500kWh of electricity. Whether that works out cheaper depends entirely on your electricity rate — on a dedicated heat pump tariff it typically does; on a standard single-rate tariff it is line-ball. Always ask installers to model this on your tariff before you decide.
The Grant, VAT and Rules Position in 2026
Running cost is only half the decision — the upfront cost has fallen for 2026. The Boiler Upgrade Scheme pays a £7,500 grant towards an air source heat pump for eligible homes in England and Wales, applied by your MCS-certified installer. The old EPC precondition (no outstanding loft or cavity-wall insulation recommendations) has been removed, so more homes now qualify. Our guide to heat pump grants in the UK sets out who is eligible and how to claim.
Heat pumps also carry 0% VAT until 31 March 2027, which lowers the installed price further. For what a switch actually costs after the grant, see our air source heat pump cost guide and weigh it against a like-for-like boiler replacement cost. The independent Energy Saving Trust publishes typical running-cost figures you can use to sense-check any installer estimate — and it is worth confirming your chosen installer is MCS-certified on the MCS database, which is required for the grant.
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