Boiler vs Air Source Heat Pump:
Which Is Better for Your Home?
Boilers are still the most common heating system in many UK homes, but air source heat pumps are becoming more popular as homeowners look for efficient, lower-carbon heating. Both systems can heat your home and hot water, but they work in very different ways.
This guide compares boilers and air source heat pumps by efficiency, running costs, installation, suitability, grants, and long-term value, so you can understand which option may be better for your property.
Quick Answer: Boiler or Air Source Heat Pump?
A boiler may be better if you need a quick, lower-cost replacement and your existing heating system is working well. An air source heat pump may be better if your home is suitable, well-insulated, and you want a more efficient, lower-carbon heating system for the long term.
Gas boiler vs air source heat pump.
Around 85%–94%
Modern Gas Boiler
Burns gas to produce heat, with some energy lost through flue gases and system operation.
Around 300%–400%
Air Source Heat Pump
Uses electricity to move heat from outside air into your home, often delivering 3–4 units of heat for every 1 unit of electricity used.
Depends on gas prices
Gas Boiler
Running costs are linked to gas tariffs, boiler efficiency, insulation levels and heating habits.
Can be lower with smart use
Heat Pump
Best performance comes from good design, correct sizing, low-flow temperatures and using smart electricity tariffs where available.
Usually lower upfront
Boiler Installation
A boiler replacement is typically less expensive upfront, especially when the existing heating system is already suitable.
Higher upfront investment
Heat Pump Installation
Installation can cost more because it may include system design, cylinder upgrades, radiator checks and electrical work.
Limited support
Gas Boiler
Traditional boiler replacements generally have fewer funding options compared with low-carbon heating upgrades.
Up to £7,500 support
Air Source Heat Pump
Eligible homeowners may be able to access support through schemes such as the Boiler Upgrade Scheme, subject to property and scheme criteria.
Uses fossil fuel
Gas Boiler
Produces carbon emissions on-site because it burns natural gas to heat your home and hot water.
Low-carbon heating
Heat Pump
Runs on electricity and can significantly reduce home heating emissions, especially as the UK electricity grid becomes cleaner.
Fast, high-temperature heat
Gas Boiler
Often heats radiators quickly using higher water temperatures, which many homeowners are already familiar with.
Steady, consistent warmth
Heat Pump
Works best by maintaining a comfortable temperature over longer periods using lower flow temperatures.
Annual service recommended
Gas Boiler
Requires regular servicing to check combustion, safety controls, flue condition and overall performance.
Low-maintenance system
Heat Pump
Still needs periodic servicing, but there is no gas combustion, flue or carbon monoxide risk from the heating unit itself.
Around 10–15 years
Gas Boiler
Typical lifespan depends on servicing, usage, water quality and installation quality.
Around 15–20 years
Air Source Heat Pump
Can offer a longer service life when correctly designed, installed and maintained.
Gas Boiler
Homes looking for a familiar heating system, lower upfront cost and a straightforward replacement where gas heating is already installed.
Air Source Heat Pump
Homeowners wanting a future-ready, efficient, low-carbon heating system with long-term energy and sustainability benefits.
