Heat pump vs boiler: running costs
No slogans, just the October 2026 price maths. Enter your home’s heat demand and see what a gas boiler and a heat pump each cost to run — per year and over 15 years.
Figures checked October 2026 Estimate
Assumes a 90%-efficient modern gas boiler and flat energy prices over 15 years. Excludes servicing and the gas standing charge — which you could drop entirely (29.68p/day ≈ £108/yr) if the heat pump also does your hot water and you remove the gas meter.
The honest October 2026 answer
Electricity at 26.32p costs about 3.3× gas at 7.97p per unit. A gas boiler turns each unit into ~0.9 units of heat; a heat pump at SCOP 3.0 turns each unit into 3. Divide one by the other and the two land almost exactly level — at the October 2026 price cap, a well-installed heat pump costs about the same to run as a modern gas boiler. Anyone telling you it’s dramatically cheaper (or dramatically dearer) at capped prices is selling something.
What tips the balance: a SCOP of 3.5 instead of 2.7 (design and radiator sizing, not the badge on the box); a heat-pump or time-of-use electricity tariff below the cap; solar panels generating the electricity; ditching the £108/yr gas standing charge; and the £7,500 Boiler Upgrade Scheme grant, which at current install prices does more for the comparison than a decade of running-cost differences. The decisive argument is carbon: a heat pump emits far less per unit of heat today and less every year as the grid decarbonises, while a boiler’s emissions are fixed for life.
So which should you choose?
If your boiler has years of life left, the carbon case alone may not justify ripping it out — insulate first and plan the switch for when it dies. If you’re replacing anyway, are off the gas grid (oil and LPG are far pricier per unit than gas), or are renovating, the heat pump case is strong: similar running costs, the grant, 0% VAT to March 2027, and no gas standing charge. Model the install side in the heat pump cost calculator and the boiler alternative in the boiler cost calculator.
Heat pump vs boiler questions
Why are heat pumps efficient but not cheaper to run?
Because the UK prices electricity at ~3.3× gas per unit while a heat pump is ~3.3× as efficient as a boiler. The efficiency advantage is real — it’s currently spent offsetting the price ratio. As grid electricity gets cheaper per unit relative to gas, heat pumps pull ahead.
What SCOP will I actually get?
A properly designed system in a reasonably insulated home: 3.0–3.5 (estimate). Undersized radiators, high flow temperatures and poor controls drag it toward 2.5. The MCS design calculation is what protects you — ask to see it.
Does a heat pump work with radiators?
Yes, if they’re sized for lower flow temperatures — many homes need a few larger radiators (a few hundred pounds each). Underfloor heating is ideal but not required.
Ready for real prices?
Calculators give you the ballpark. Get free, no-obligation quotes from MCS-certified UK installers and compare them against these numbers.