Like millions of other UK families, are you also torn between converting to electric boilers or continuing with the gas ones? Well, as gas boiler prohibitions arrive in 2035 and energy bills remain sky high, thousands of UK homeowners are considering their choices. But it’s hard to say which one really makes sense for your house and budget.
Let’s cut through all you need to know about electric boilers and gas boilers, from their running costs and installation costs to their efficiency ratings and real-world efficiency. So you can make an informed decision.
What are the Main Differences Between Electric and Gas Boilers?
An electric boiler warms up water with electrical resistance elements, just like a huge electric kettle for your heating system. No burning, no fire, and no flue required to escape exhaust gases. You just require an electrical supply, and you’re away.
Gas boilers, however, function by igniting natural gas in a burner in a combustion chamber. The heat is transmitted through a heat exchanger to heat your water, but you’ll require a gas supply pipe, ventilation, and a flue system to eliminate exhaust gases safely.
Electric Boiler vs Gas Boiler Running Costs
Here’s where things get interesting and expensive. Running costs are where your heating choice really hits your bank account month after month.
What Do Current Energy Prices Look Like?
As of 2025, the energy price cap means electricity costs about 27p per kWh, while gas comes in at just 7p per kWh. That’s nearly a 4:1 difference. Ouch.
So what does this mean for your actual heating bills?
For a small 1-2 bedroom property:
- Electric boiler: £1,400-£1,700 per year
- Gas boiler: £620-£890 per year
You’ll pay around £780-£810 more with electric
For a medium 3-bedroom home:
- Electric boiler: £1,800-£2,200 per year
- Gas boiler: £890-£1,100 per year
That’s £910-£1,100 extra annually
For a large 4+ bedroom house:
- Electric boiler: £2,200-£3,000 per year
- Gas boiler: £1,100-£1,260 per year
You’re looking at £1,100-£1,740 more per year
Electric Boiler Cost Per Month
Breaking it down monthly makes it easier to budget. Here’s what you can expect:
- 1-bedroom flat: £70-£95 per month
- 2-bedroom house: £95-£135 per month
- 3-bedroom semi: £130-£180 per month
- 4-bedroom detached: £170-£250 per month
Got an Economy 7 tariff? Smart timing could save you 20-30% by heating during off-peak hours (usually 11 pm-7 am) when electricity drops to around 15-20p per kWh. Every little helps, right?
Electric Boiler vs Gas Boiler Price: Installation and Purchase Costs
Running costs tell one story, but what about getting the thing installed in the first place?
What Are the Purchase Costs?
The buying costs of both heating systems are devastatingly vast, as are the savings on going for each.
Electric Boilers
These range from £800 to £2,500 for most homes. While the Combi models sit at £800-£1,500, system boilers cost £1,200-£2,000. If you need high capacity by any chance, you might need to pay £2,500-£4,500+.
Gas Boilers
These actually cost a bit less upfront: £600 to £1,700 typically, while Combi gas boilers run £600-£1,500, and system models cost £775-£1,250.
Installation Cost: The Full Picture
Now, it gets interesting: an electric boiler installation generally costs from £500 to £2,000. But here’s the kicker: if your property needs a three-phase power supply upgrade, add another £3,000-£8,000. Ouch.
This will usually cost within the range of £1,000 to £2,500. A simple combi swap might cost £1,000-£1,500, while a full system conversion or complicated flue work could push you toward £2,500.
The bottom line is neither option is exactly cheap, and your specific property setup is going to make a big difference to the final bill.
Gas and Electric Boiler Efficiency: What the Numbers Really Mean
Ever seen those efficiency ratings and wondered what they actually mean for your heating bills?
Point-of-Use Efficiency
In terms of efficiency, electric boilers win hands down: they are 100% efficient, converting all of the electricity into heat.
Virtually nothing gets wasted. Gas boilers, even the best modern condensing models, hit around 90-95% efficiency because some energy escapes through flue gases.
But wait; there’s a catch.
Lifespan of Electric and Gas Boilers: Which Lasts Longer?
In general, electric boilers will run strongly for 15-25 years. With fewer moving parts and no combustion process to wear things down, they’re built to go the distance. Some manufacturers don’t even specify a maximum lifespan.
Gas boilers tend to last 10-15 years before replacement is needed, since all of the mechanical components and the heat generated from combustion cause more wear and tear.
You’ll need regular maintenance to hit the upper end of that range, and you may need to replace heat exchangers or burners along the way.
Think about it: one electric boiler could outlast two gas boilers. That’s another installation cost and all the hassle saved.
Closing Thoughts
The decision between electric and gas boilers is not one-size-fits-all. For running costs and heating performance, gas boilers presently always come out on top, making them ideal for larger properties and households on a tight budget.
For safety, environmental impact, and future-proofing, electric boilers excel, especially for smaller, well-insulated homes. Think about the size of your property, the quality of its insulation, and whether you are on the gas network.
Consider your budget for both installation and monthly running costs. And don’t forget your values; if going green matters to you, electric heating powered by renewables could be the right choice despite the higher bills.
Frequently Asked Questions
Electric boilers fall under the umbrella of an electric heating system. Much more expensive to run than gas boilers, as it costs around 27p per kWh compared with 7p per kWh for gas, modern electric boilers with smart controls can, on the other hand, be more efficient than electric storage heaters.
No, electric boilers do not need a Gas Safe registered engineer. Their installation is carried out by qualified electricians only. This often makes finding installers easier, and the installation costs could be cheaper than with gas boilers, whose installations legally demand a Gas Safe certification.
Usually, yes, but the electrical supply in your home might need an upgrade first. Most homes have single-phase electricity, which is fine for smaller electric boilers. The larger properties will require a three-phase supply that could be installed for £3,000-£8,000. A qualified electrician can assess your property.
Electric combi boilers work well for smaller households, 1-3 people, with modest hot water demands. For larger families, or where there may be more than one bathroom in use at the same time, the flow rates might be inadequate compared to a gas combi boiler. Consider your peak usages carefully.
