Electric Boiler vs Gas Boiler

Choosing between an electric and gas boiler isn’t just a technical decision — it affects your energy bills, your carbon footprint, and how easy your heating system is to live with day to day. Here at Plus Heat, we’ve broken down every key difference so you can make the right call for your home.

What Is the Difference Between a Gas Boiler and an Electric Boiler?

Both types heat your home and provide hot water on demand. The difference is the fuel source — and that single factor changes almost everything else: running costs, installation requirements, efficiency, and environmental impact.

How Does a Gas Boiler Work and Is It Worth It?

Gas boilers remain the dominant heating choice in UK homes, with around 1.7 million units installed annually. They run on mains natural gas (or LPG in off-grid areas), heat water quickly, and handle high demand well — making them well suited to larger properties with multiple bathrooms.

Key advantages:

• Significantly cheaper to run — gas costs approximately 7p per kWh compared to around 27p for electricity

• Annual running costs average around £890, compared to approximately £1,700 for electric

• Handle simultaneous high hot water demand across multiple outlets

• All new UK gas boilers must be A-rated — at least 90% efficient

• Faster water heating for larger, busier households

Drawbacks:

• Require a mains gas connection — not suitable for off-grid properties

• Produce CO₂ emissions (0.216 kg per kWh)

• Annual service required — typically £60–£110

• Small carbon monoxide risk if poorly maintained or unserviced

• More moving parts mean more potential for wear over time

How Does an Electric Boiler Work and Who Is It Best For?

Electric boilers heat water using electrical elements — no flue, no gas supply, no combustion involved. Installation is simpler and they operate almost silently, making them a practical choice for flats, smaller properties, and off-grid homes.

Key advantages:

• Near-perfect efficiency of 99–100% at point of use

• No flue or gas supply needed — simpler, less disruptive installation

• Zero direct emissions — genuinely low-carbon when paired with solar panels or a green electricity tariff

• Fewer moving parts — lower maintenance requirements and a longer average lifespan of 15–25 years versus 10–15 years for gas

• No carbon monoxide risk

Drawbacks:

• Electricity costs roughly four times more per kWh than gas

• Higher annual running costs — approximately £1,700 on average

• Struggle with simultaneous demand — not suited to homes with multiple bathrooms in use at once

• Won’t function during a power cut

• Less suited to larger properties with high heating demand

Gas Boiler vs Electric Boiler: Running Costs, Efficiency and Lifespan Compared

Are Electric Boilers More Efficient Than Gas Boilers?

Electric boilers win on point-of-use efficiency — 99–100% versus 90–95% for gas. But this doesn’t tell the whole story. Electricity is generated largely from fossil fuels and transmitted via the national grid, meaning upstream carbon losses are significant. The carbon intensity of grid electricity sits at around 0.519 kg CO₂/kWh compared to 0.216 kg for gas — meaning that despite higher point-of-use efficiency, electric boilers currently carry a larger carbon footprint when running on standard grid electricity.

That changes meaningfully if you generate your own renewable electricity through solar panels — in that scenario, an electric boiler becomes a genuinely low-carbon heating solution.

What Are the Different Types of Electric Boiler Available in the UK?

• Electric combi boiler — heats water on demand, compact, no storage tank needed; ideal for smaller homes and flats

• Electric storage boiler — stores hot water in an insulated tank; suited to homes with consistent hot water demand

• Dry core storage boiler — heats bricks overnight on off-peak electricity and transfers heat to water; cost-effective on time-of-use tariffs

• Electric CPSU (Combined Primary Storage Unit) — high-capacity unit for larger properties with significant simultaneous hot water demand

What Are the Different Types of Gas Boiler Available in the UK?

• Combi gas boiler — the most popular UK choice; heats water on demand with no storage tank; ideal for small to medium homes

• System gas boiler — works with a separate hot water cylinder; well suited to homes with multiple bathrooms needing simultaneous hot water

• Regular (heat-only) gas boiler — traditional setup with both a hot water cylinder and cold water tank; most common in older properties with existing infrastructure

How Can I Tell If My Boiler Is Gas or Electric?

Not sure what you have? Check these:

• Look for a flue pipe — a white plastic or metal pipe exiting through an outside wall indicates a gas boiler

• Check the pipework — gas boilers have a gas supply pipe (usually yellow or copper) connected to them

• Look for an ignition — pilot lights and electronic ignition systems are only found on gas boilers

• Check your meter — if your boiler runs on a dedicated circuit breaker and there’s no gas meter at the property, it’s electric

Should I Choose a Gas or Electric Boiler for My Home?

Choose a gas boiler if you’re connected to the mains gas grid, have a medium-to-large property with more than one bathroom, and want to keep running costs as low as possible.

Choose an electric boiler if you’re off-grid, live in a flat or smaller property, generate your own renewable electricity, or want a simpler installation with lower ongoing maintenance requirements.

Frequently Asked Questions About Gas and Electric Boilers

Will gas boilers be banned in the UK?

The UK government has confirmed that gas boilers will be phased out in new-build homes, with heat pumps becoming the default. For existing homes, replacing a like-for-like gas boiler is still permitted. Policy continues to develop, so it’s worth keeping an eye on government announcements if you’re planning a boiler replacement in the coming years.

Is an electric boiler cheaper to install than a gas boiler?

Marginally — electric boilers average around £3,250 to install versus £3,450 for gas. However, if new gas pipework, a flue, or a gas meter connection is needed, installation costs for gas rise considerably.

Can I switch from a gas boiler to an electric boiler?

Yes, but it’s worth running the numbers first. The difference in running costs — roughly £800 more per year for electric — means switching rarely makes financial sense unless you’re off-grid or generating your own renewable electricity.

Do electric boilers need an annual service?

Electric boilers don’t require a mandatory annual service in the same way gas boilers do — there’s no combustion involved and no gas safety inspection required. That said, periodic maintenance checks are still worthwhile to keep the system running efficiently and catch early signs of component wear.

Not sure which type of boiler suits your home? Call the Plus Heat team on 0808 164 2892 — our heating experts can help you make the right choice, and our boiler cover plans keep whichever system you choose protected year-round.