Heat Pump vs Gas Boiler Running Costs: An Installer’s Insider Guide for UK Homes (2025)
Discover the real running cost differences between heat pumps and gas boilers in UK homes. Written by experienced ECO4 installers, this guide reveals practical savings, common mistakes, and how to check your eligibility for free upgrades.
Heat Pump vs Gas Boiler Running Costs: The Real Numbers Installers Wish UK Homeowners Knew
Introduction: Cutting Through the Confusion on Heat Pump vs Gas Boiler Running Costs
Every week, UK homeowners ask me: “Are heat pumps really cheaper to run than gas boilers?” It’s a fair question—especially with all the conflicting advice online. As someone who’s replaced hundreds of gas boilers and fitted dozens of heat pumps under the ECO4 scheme, I’ve seen the numbers, the savings, and the surprises up close. Today, I’ll break down the real-life running costs, expose common misconceptions, and share the practical details most guides miss—so you can make the best decision for your home and wallet in 2025.
Heat Pump vs Gas Boiler Running Costs: The Installer’s Deep Dive
Let’s Talk Numbers: What You’ll Actually Pay
- Gas Boiler Average Running Cost: About £1,302–£1,500 per year for a typical UK home (includes fuel, maintenance, and servicing)[1][5].
- Heat Pump Average Running Cost: About £920–£1,156 per year (well-installed, well-insulated home, including maintenance)[1][5].
These figures reflect real-world averages as of June 2025. Gas is still cheaper per kWh than electricity, but heat pumps are 3–4 times more efficient. This is why, in practice, a well-fitted heat pump can cost less to run than a gas boiler—even with higher electricity rates[2][5].
Installer's Pro-Tip
Heat pumps only deliver these savings if your home is well-insulated. I’ve visited properties where a heat pump was installed, but with poor insulation, the bills were actually higher than the old gas boiler. Before switching, check your EPC rating and tackle insulation first—ECO4 grants can help with both.
What Drives the Running Costs?
- Energy Prices: Gas averages around 5.5p per kWh; electricity about 22p per kWh[3]. But heat pumps turn 1kWh of electricity into 3–4kWh of heat.
- Efficiency: Modern gas boilers: 85–90% efficient. Heat pumps: 300–400% (COP 3–4)[1][3][5].
- Home Insulation: A heat pump in a draughty house will guzzle electricity. In a well-insulated home, it shines.
- Heating Habits: If you like the house toasty 24/7, expect higher running costs with either system.
Upfront Costs & Grants (A Quick Note)
- Gas Boiler: £1,700–£3,500 installed. Quick, often done in a day[3].
- Heat Pump: £10,000–£22,000 (air source, before grants). Boiler Upgrade Scheme offers up to £7,500 off. ECO4 can cover most or all costs for eligible households[1][3].
Real-World Example: What I’ve Seen in UK Homes
In early 2025, we helped a family in Leeds swap out their 15-year-old gas boiler for a new air source heat pump. Their home had recently been upgraded with cavity wall and loft insulation through the ECO4 scheme. Their annual heating bill dropped from £1,420 to just under £1,000—a saving of over £400 per year. But in a similar house nearby, with poor insulation, the heat pump actually increased bills until we sorted out the drafts and insulation first.
Common Mistake to Avoid
Don’t assume a heat pump will always save you money. If your home’s insulation is poor, your heat pump will work overtime. We’ve seen homeowners shocked by their first winter bills after a DIY heat pump install in a leaky Victorian terrace. Always get an expert assessment first.
How to Maximise Your Savings: Insider Advice
- Check Your Insulation: Upgrade before switching to a heat pump. Under ECO4, we can often insulate homes at no upfront cost.
- Get a Proper Heat Loss Calculation: A heat pump must be sized for your property. Oversized or undersized units waste energy and money.
- Use Smart Controls: Modern thermostats and weather compensation boost efficiency for both systems.
- Combine with Solar (if possible): If you have solar PV, you can run your heat pump for a fraction of the standard cost[5].
- Maintenance Matters: Both boilers and heat pumps need annual servicing to stay efficient. Neglect leads to higher bills.
FAQs: Installer Answers to Your Top Running Cost Questions
- Q: Will a heat pump always be cheaper to run than a gas boiler?
A: Only if your home is well insulated and the system is sized and installed properly. Otherwise, you may not see savings[3][5]. - Q: Are running cost savings worth the hassle of switching?
A: If you qualify for grants and your home is ready, yes—the long-term savings and lower carbon footprint are significant[1][5]. - Q: How do maintenance costs compare?
A: Both require annual checks. Heat pump servicing is usually similar in price to boiler servicing. - Q: Can I get ECO4 or BUS help for both systems?
A: ECO4 focuses on low-income or vulnerable households, covering insulation and heating upgrades (including boilers and heat pumps). The Boiler Upgrade Scheme is specifically for heat pumps, with up to £7,500 off[1][3]. - Q: What if I have an older property?
A: Older homes often need insulation upgrades first. Otherwise, running costs for heat pumps can be higher than expected.
Conclusion: What’s the Best Choice for Your Home in 2025?
The numbers are clear: in a well-insulated home, heat pumps can be cheaper to run than gas boilers—but the key is proper installation and preparation. At applyfreeboiler.co.uk, we’ve seen firsthand how ECO4 grants can transform cold, draughty homes into efficient, comfortable spaces—often at no upfront cost to you. Don’t risk disappointment or higher bills by skipping the prep work. Let our accredited team guide you through every step—from insulation to heat pump or boiler install—so you get real savings, not just promises.
Information correct as of 23/06/2025. Government schemes and energy prices can change—always check with an accredited installer.
