The honest answer is: it depends. Heat pumps aren’t always cheaper to run than a gas boiler, and they aren’t always more expensive either. Running cost comes down to four things, and once those line up, a heat pump matches or beats gas on bills.
The four things that decide your running cost
- Your energy tariff. A heat pump on a flat single-rate tariff costs more to run than the same heat pump on a time-of-use tariff like Octopus Cosy. The pricing structure of your electricity supply matters more than people realise.
- The age and efficiency of your boiler. A modern A-rated gas boiler running at peak efficiency is a different comparison from a 15-year-old boiler running at 70%. The older the boiler, the easier a heat pump wins.
- The quality of your heat pump install. A poorly designed system with the wrong kW, wrong flow temperatures, or short-cycling controls will run inefficiently and burn through electricity. A properly designed install will hit its SCOP (seasonal coefficient of performance) target.
- The heat loss of your property. A leaky old house with no loft insulation will cost more to heat regardless of what’s doing the heating. A well-insulated property gets the most out of a heat pump.
What our engineer says
“There is no easy definition, but there are multiple factors to take into consideration: your energy tariff, the age of your boiler, the quality and installation of your heat pump, and your overall heat loss of the building. With solar battery support, it’s an absolute no. But as an overall design, it should not cost you any more to run.”
Talk to us
Get in touch for a heat pump consultation and we’ll work out the right design for your property. If funding is on your mind, our 2026 Boiler Upgrade Scheme offer covers most of the install cost.