How Much Electricity
Does a Heat Pump Use?
A heat pump uses electricity to move heat rather than to generate it directly. The result is 3 to 5 kWh of heat output for every 1 kWh of electricity input. For a typical UK home, that means £700 to £1400 in annual electricity for whole-home heating plus hot water.
An air source heat pump uses 3,000 to 6,000 kWh of electricity per year to heat a typical UK home plus provide hot water, depending on house size, insulation plus how the system is run. At the current Q2 2026 Ofgem unit rate of 24.7p per kWh that means £741 to £1,482 per year. The same home heated by direct electric heaters would cost 3 to 5 times more. Heat pumps achieve this through their coefficient of performance (COP) of 3 to 5, meaning they deliver 3 to 5 kWh of heat per 1 kWh of electricity input.
The figures that matter
Annual electricity
Range across UK home sizes plus insulation levels for whole-home heating plus hot water.
COP
Coefficient of performance. The multiplier of heat output to electricity input.
Annual cost
At the current 24.7p Ofgem cap. Typical 3-bed UK semi sits roughly mid-range.
Effective heat cost
Cost per kWh of heat delivered to the home. Far cheaper than direct electric heating.
Four things to consider
COP is the key metric
Higher COP means less electricity per kWh of heat. Look for COP 4+ for best running costs.
Insulation halves bills
A well-insulated home uses 30 to 50 percent less heating electricity than a poorly insulated equivalent.
Sizing is critical
Oversized heat pumps cycle inefficiently. Undersized ones cannot keep up. Both increase running costs.
Run continuously, not on demand
Heat pumps work best at low steady output. Bursting on plus off like a gas boiler reduces efficiency.
Where the electricity goes in a heat pump system
A heat pump moves heat from outside (air or ground) into your home. The work it does is mostly compression, not generating heat directly. That is why it can deliver 3 to 5 kWh of heat per kWh of electricity input.
Real numbers at 24.7p per kWh (Q2 2026 Ofgem cap):
- Small 2-bed flat (well insulated, 8,000 kWh heat demand): 2,000 to 2,700 kWh electricity, £494 to £667 per year.
- Standard 3-bed semi (average insulation, 12,000 kWh heat demand): 3,000 to 4,000 kWh electricity, £741 to £988 per year.
- Larger 4-bed detached (average insulation, 16,000 kWh heat demand): 4,000 to 5,500 kWh electricity, £988 to £1,358 per year.
- Older 4-bed plus poorly insulated (20,000+ kWh heat demand): 5,500 to 6,500 kWh electricity, £1,358 to £1,605 per year.
Air source vs ground source on running cost. Ground source heat pumps achieve higher COP (4 to 5) because ground temperature is more stable than air temperature. Air source COP varies between 4.5 in mild weather plus 2.5 in cold snaps. Across a UK winter the average works out to 3 to 4. Ground source costs more to install (typically £18,000 to £25,000 versus £7,500 to £13,000 for air source) but saves around 15 percent on running costs over the system life.
Hot water plus space heating split. Roughly 70 to 80 percent of heat pump electricity goes on space heating, 20 to 30 percent on hot water. The hot water side is where heat pump efficiency is lowest because the higher target temperature (50°C+) reduces COP. Some systems use the heat pump for space heating plus a separate immersion or electric boost for the hot water tank.
What pushes heat pump running costs higher:
- Poor insulation. Heat demand drives every running cost figure. Insulate first.
- Oversized or undersized system. Both cycle inefficiently. Sizing should be done by a competent installer based on a proper heat loss calculation.
- Wrong radiator sizing. Heat pumps work best at lower flow temperatures (35 to 50°C) which means larger radiators or underfloor heating.
- Old single-glazed windows. Each window can lose 10 percent of room heat. Adds up across the home.
- Cold winters. COP drops in cold weather so the same heat output costs more electricity.
Real number ranges
Annual heat pump electricity cost (UK 2026)
How a heat pump runs across a UK winter day
Boost mode
Heat pump warms house from overnight setback. Higher draw for 1 to 2 hours. 2 to 3 kWh used.
Steady low draw
Heat pump cycles at low output to maintain temperature. 0.5 to 1 kW continuous.
Slight increase
External temperature drops, heat pump works slightly harder. Up to 1.5 kW continuous.
Setback
Lower target temperature. Heat pump runs at minimum draw. Daily total 15 to 25 kWh in winter.
Four ways to cut heat pump running costs
Insulate the home first
Loft insulation, cavity wall, draught-proofing plus double glazing all reduce heat demand. Every kWh saved is roughly 5p saved at COP 4.
Run at low flow temperature
Heat pumps achieve higher COP at lower flow temperatures. Set the system at 35 to 45°C if radiators allow.
Avoid the immersion boost
Direct electric immersion boosts cost 24.7p per kWh of heat versus 5p to 10p through the heat pump. Use immersion only when essential.
Schedule with weather forecasts
Pre-heat the home before cold snaps. Heat pumps run more efficiently in milder weather.
Compare the options
Air source heat pump
- ✓COP 3 to 5 across the year. Heat output 3 to 5x electricity input.
- ✓5p to 10p per kWh of heat delivered at the current Ofgem rate.
- ✓£741 to £988 per year for typical 3-bed semi.
- ✓£7,500 grant available through the Boiler Upgrade Scheme.
- ✓20+ year typical lifespan. Outperforms gas boilers on durability.
Direct electric heating
- ✗COP 1.0. Direct electric. 1 kWh in equals 1 kWh out.
- ✗24.7p per kWh of heat delivered at the same Ofgem rate.
- ✗£2,500 to £3,500 per year for the same heat demand.
- ✗No grant for whole-home direct electric heating systems.
- ✗Lower install cost but much higher running cost. Long-term cost is significantly worse.
Heat pumps are the lowest-running-cost option for whole-home UK heating in 2026. Our full Appliances hub covers running costs across every major UK household appliance.
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This article is one chapter inside our complete Appliances knowledge base. The hub covers running costs across every major household appliance from kettles to heat pumps.
More on appliance running costs
Three further heating cost articles in the same hub group cover related questions. The first is how much electric do electric heaters use for the direct electric comparison. The second covers how much electric does a heater use across all heater types. The third is how much electricity does a house use per day uk for the household total context.