Heat Pumps vs. Gas Boilers : Which is Cheaper to Run in the UK? (2025)

With energy prices climbing and the UK pushing for net-zero by 2050, homeowners are rethinking their heating options. Gas boilers have long dominated UK homes, but heat pumps are gaining traction as a greener, potentially cheaper alternative. So, are heat pumps really more cost-effective to run than gas boilers? Let’s break down the costs, efficiency, and long-term savings to help you decide.

Why Compare Heat Pumps and Gas Boilers?

• Gas Boilers: Found in ~80% of UK homes, they’re affordable to install but rely on volatile gas prices and emit significant CO₂.
• Heat Pumps: Run on electricity, boast higher efficiency, and align with the UK’s plan to phase out new gas boilers by 2035.

Here’s a detailed look at both options, focusing on running costs, installation, and long-term value.

1. Gas Boilers: The Traditional Choice

Why Are They Popular?

• Affordable Upfront: Installation costs £1,500–£3,500, including labour.
• Quick Heating: Radiators warm up fast, ideal for older homes.
• No Major Upgrades: Works with existing systems, no need for insulation or radiator upgrades.

The Downsides

• Rising Costs: Gas prices have surged ~130% since 2021, with average annual running costs of £900–£1,300 (based on a typical 3-bedroom home).
• Efficiency: Modern boilers achieve 90–94% efficiency, but some heat is lost through flues.
• Environmental Impact: Gas heating accounts for ~15% of UK CO₂ emissions.
• Future Risk: New gas boiler installations may be banned by 2035, reducing resale value.

 

2. Heat Pumps: The Future of Heating

How Do They Work?

Heat pumps extract warmth from the air or ground, using electricity to deliver 3–4 times more heat per unit of energy (like a fridge in reverse). They provide steady, consistent warmth, though they heat up more slowly than boilers.

Why Consider Them?

• High Efficiency: 300–400% efficiency (1 kWh of electricity = 3–4 kWh of heat).
• Lower Running Costs: £550–£950 per year for a well-insulated home, assuming current electricity prices.
• Eco-Friendly: Near-zero emissions when paired with renewable electricity.
• Grants Available: The UK’s Boiler Upgrade Scheme offers £7,500 to offset installation costs.

The Catch

• Higher Upfront Cost: £8,000–£16,000 for air-source heat pumps, depending on home size and system.
• Home Upgrades: Best suited for well-insulated homes (EPC rating C or higher) with larger radiators or underfloor heating.
• Slower Heating: May feel less responsive in poorly insulated homes.

Cost Comparison at a Glance

Factor	Gas Boiler	Heat Pump
Installation Cost	£1,500–£3,500	£8,000–£16,000 (minus £7,500 grant)
Annual Running Cost	£900–£1,300	£550–£950
Efficiency	90–94%	300–400%
CO₂ Emissions	High (~15% of UK emissions)	Near-zero (with green energy)
Lifespan	10–15 years	15–20 years
Future-Proof	At risk (2035 ban)	Aligned with net-zero goals

Note: Costs assume a 3-bedroom home with average insulation and 2025 energy prices (gas: ~10p/kWh, electricity: ~28p/kWh).

Which Is Cheaper to Run?

• Short-Term (1–3 Years): Gas boilers are cheaper to install but more expensive to run. Heat pumps save £350–£450 annually on energy bills, but high upfront costs mean longer payback periods.
• Long-Term (5–10 Years): Heat pumps win, especially with the £7,500 grant. Falling electricity prices (due to growing wind and solar) and rising gas prices make heat pumps increasingly cost-effective.
• Payback Period: With grants, heat pumps break even in 5–8 years, faster in well-insulated homes.

Is a Heat Pump Right for You?

Choose a Heat Pump If:

• Your home is well-insulated (EPC C or higher).
• You qualify for the Boiler Upgrade Scheme (£7,500 grant).
• You’re committed to long-term savings and sustainability.
• You plan to stay in your home for 5+ years.

Stick with a Gas Boiler If:

• You need the lowest upfront cost.
• Your home has poor insulation or outdated radiators.
• You’re moving soon and won’t see payback.

 

The Future of UK Heating

• Policy Shift: The UK’s 2035 gas boiler ban signals a move toward low-carbon heating.
• Tech Improvements: Heat pump costs are dropping, with efficiency improving yearly.
• Energy Trends: Electricity prices may stabilize as renewables grow, while gas prices remain unpredictable.

Verdict

Gas boilers are cheaper to install but costlier to run, with annual bills £350–£450 higher than heat pumps. With grants, falling tech costs, and the 2035 ban looming, heat pumps are the smarter long-term investment for most UK homes. They’re greener, cheaper to operate, and future-proof.

Ready to Switch?

The heat pump revolution is here, and 2025 is the perfect time to act. With the £7,500 Boiler Upgrade Scheme, you can slash installation costs and start saving on energy bills. Curious about your savings potential? Contact us for a free, no-obligation assessment:

We’re a TrustMark-accredited installer, ensuring professional, reliable service. Verify on TrustMark.

Call: 0203 092 9602
Email: info@interinfinity.co.uk

Make your home warmer, greener, and more affordable today!