Plan your UK heat pump the smart way

A typical 9 kW air source heat pump costs £12,500–£17,000 installed in 2026 before the £7,500 Boiler Upgrade Scheme grant. After the grant, most three-bedroom UK homes pay £5,000–£9,500 net. Ground source systems cost £20,000–£35,000 installed, with the same £7,500 grant.

Yes. The Boiler Upgrade Scheme was extended to 2028 in the 2024 Spring Statement, with funding boosted to £1.5 billion. It's £7,500 for air source and ground source heat pumps in England and Wales, applied directly by your MCS-certified installer — you don't claim it yourself. Scotland uses the Home Energy Scotland scheme (also up to £7,500) and Northern Ireland uses NI Boiler Replacement Scheme.

Use the heat pump size calculator. The rough rule of thumb:

• Modern, well-insulated home (post-2010 build regs): ~30 W per m²
• Standard 1990–2010 UK home: ~55 W per m²
• Pre-1980 home with cavity insulation: ~90 W per m²
• Solid-wall, listed, or no insulation: 100–120 W per m²

So a 100 m² standard 3-bed semi needs roughly 5.5 kW × 1.5 winter design margin = ~8 kW. Your MCS installer will run a full room-by-room heat loss calculation before quoting.

On the standard Ofgem price cap (gas at 6.99 p/kWh, electricity at 26.35 p/kWh as of Oct 2025), a well-installed air source heat pump with SCOP 3.0+ runs at roughly the same annual cost as a modern gas boiler. On a time-of-use tariff such as Octopus Cosy or Octopus Go, heat pumps typically cost 20–35% less per year than gas. A poorly-installed heat pump (SCOP 2.4) on the standard tariff can actually cost more than gas — installation quality matters enormously.

A straightforward air source heat pump replacement takes 2–4 working days on site, plus 2–8 weeks lead-time for the installer survey, MCS paperwork, and BUS grant submission. Ground source heat pumps require borehole drilling and take 1–2 weeks on site. Plan 8–12 weeks from first quote to commissioning.

Often yes — partially. Heat pumps work best with larger emitters because they output water at 35–50°C instead of a gas boiler's 65–75°C. Your MCS installer will run a room-by-room heat-loss calculation: rooms that already have an oversized radiator are usually fine; bedrooms and bathrooms commonly need bigger units. Budget £400–£1,500 for radiator upgrades on a typical 3-bed house. Underfloor heating is ideal but not required.