Gas boilers vs electric heat pumps: Which heating is cheaper?

Right now, a lot of us are weighing up heat pump central heating against traditional gas systems and wondering where the real value sits. So let’s unpack the big question: heat pump vs gas boiler. Which is actually cheaper? Spoiler alert: it depends. But there are some clear patterns worth sharing, and depending if you already have green-home technology, like solar panels, home batteries, or time of use tariffs, the savings potential is enormous.

The great heating debate: Gas vs electricity.

For decades, gas has been the go-to for heating. It’s familiar, widely available, and historically cheaper per unit of energy. Electricity, on the other hand, often costs more per kWh, which is what you're billed on (but that’s only half the story.)

Recent UK price cap data shows electricity costs several times more per unit than gas, which is why gas heating has traditionally looked cheaper at first glance. But, heating systems are not just about fuel price. They’re about how well that fuel gets turned into heat inside our homes. And this is where things get interesting.

Understanding efficiency: the "secret" to lower bills.

When we talk about "cheaper," we usually think about the price on the tin. But in the world of heating, it’s not just about what you pay for the fuel; it’s about how much of that fuel actually ends up as warmth in your living room.

Gas boilers: the 90% rule.

Modern condensing gas boilers are impressive pieces of kit. Most operate at roughly 90% efficiency or higher,₁ meaning about 90p of every £1 spent on gas becomes heat in your home.

The remaining energy escapes through the flue as hot exhaust gases. It’s not wasted by design, it is simply part of combustion physics. Older boilers, for context, are only about 60–70% efficient. In other words, for every £1 you spend on gas, about 30p to 40p literally disappears into thin air through the flue pipe on the side of your house. We’ve accepted it for years, but in 2026, we’re all looking for ways to make our money go further.

Heat pumps: the 300%+ rule.

Now, heat pumps play a different game. Instead of generating heat, they move heat from outside air into your home. A heat pump doesn’t actually "create" heat by burning something. Instead, it’s a master of relocation. It acts like a thermal magnet, pulling heat from the outside air (yes, even when it feels chilly to us!) and moving it into your home. And it doesn't need to be 'warm' outside. Heat pumps are popular in Scandinavian countries where the temperature is regularly in the minus figures!

This impressive efficiency is measured using something called the Coefficient of Performance (COP) or seasonal COP (SCOP). Many systems achieve real-world averages somewhere around 2.5–3.5, depending on the home and conditions. Academic reviews show average COP values around 3 or higher in many setups.

The comparison: a game of numbers.

Let’s put them side-by-side in a quick huddle:

• Gas boiler: 1kW in → ~0.9kW of heat produced.

• Heat pump: 1kW in → 3kW to 4kW of heat produced.

So while electricity costs more per unit, heat pumps often deliver more heat per pound spent, depending on your home and tariff.

Environmental impact and the carbon footprint.

We’d be pulling the wool over your eyes if we didn't mention the planet. While we’re focusing on the "cheaper" side of things, the "greener" side is part of the same coin.

A gas boiler is a combustion engine in your kitchen. It burns fossil fuels, releasing carbon dioxide every time it clicks on. A heat pump, however, runs on electricity. As our UK grid gets more of its "juice" from wind, solar, and nuclear, your heating naturally gets cleaner over time without you lifting a finger.

So if you've already got solar and/or a home battery system, you can take advantage of your self-generated power right away to heat your home. If you decide to install these later down the line, they can be used to potentially lower your heating bills, and reduce your reliance on the grid, becoming more stable in terms of heating costs even when energy prices increase.

It’s a nice feeling, knowing that while you’re saving energy through efficiency, you’re also lightening your footprint. It’s not about being a "sustainability superstar" overnight; it’s about making a choice today that stays relevant for the next fifteen years.

Factors impacting your running costs.

This is where we need to be super honest. Two homes on the same street can get very different results. To get those low bills, we need to look at the big picture.

Home insulation.

Heat pumps prefer steady, low-temperature heating. They shine in homes with:

• Good loft or cavity insulation.

• Double or triple glazing.

• Draught reduction.

If heat is constantly escaping, any system will struggle. Heat pumps just show it faster. The good news is insulation upgrades often help comfort first and bills second. Warmth you can feel, savings you can see. Read more: Does my home need to be insulated to have a heat pump?

Smart tariffs.

Electric heating unlocks access to time of use tariffs. This means running heating (or hot water storage) when electricity is cheaper, often overnight or during low demand periods. Gas pricing is usually flatter, but electricity pricing can be more flexible. Our Next Pumped tariff is designed to help you make the most of your heat pump, whilst maximising savings and comfort.

If we time it right, we sometimes shift costs without changing comfort. Quiet savings, steady living.

Maintenance.

Gas systems need annual safety checks because combustion produces gases like carbon monoxide. Heat pumps do not burn fuel, so servicing is typically simpler. They still need maintenance, just different maintenance. Less flame, more fan. Less combustion, more circulation.

Heat pumps are a bit more low-maintenance. They don’t involve combustion, so there’s no "fire" to manage. While they still need a check-up to keep the warranty happy, they generally have a longer lifespan—often 15 to 20 years compared to the 10 to 12 years of a typical boiler.

Installation: thinking long-term.

Let’s address the elephant in the room: the upfront cost. Swapping a gas boiler for another gas boiler is usually the "cheaper" option on day one. But we’re looking at the long game here. A boiler replacement is usually like-for-like, and whilst it costs less, doesn't include any key system upgrades. If there's rooms in your home that are cold because radiators are undersized for example, that wont change. However, a heat pump install will include radiator and system upgrades to ensure that every room in your house is at the right temperature for absolute comfort. So whilst the overall costs may appear higher, if you factored in a bespoke property design and radiator upgrades on top of the cost of a boiler, the different isn't as great as it may first seem.

Upfront costs and the helping hand.

A heat pump vs gas boiler installation is a bigger project. It often involves bigger radiators or a new hot water cylinder. However, the government’s Boiler Upgrade Scheme (BUS) currently offers a £7,500 grant to help bridge that gap.

In many cases, this grant brings the cost of a heat pump down to a level that’s very competitive with a high-end gas boiler. We’re working hard to make this process as smooth as possible, our experts handle the paperwork for you, so the grant is deducted right from your quote. No waiting around for rebates; just a straightforward price.

The switch: easier than you think.

Many people worry that switching is like performing open-heart surgery on their house. It’s really not. When managed by experts (like us!), it’s a structured process. We’ll assess your home, take care of all the designs, certifications and importantly the BUS grant paperwork, and then get you up and running.

We’re in a transition period in the UK. Gas is the "now," but electricity is the "next." Making the switch from gas boiler to heat pump isn't just about this year's bill; it's about making your home "future-ready" so you aren't left scrambling when gas prices fluctuate or regulations change down the line.

The verdict: which is actually cheaper?

If we look at the raw data for February 2026:

• For a poorly insulated home on a standard tariff, gas might still feel slightly cheaper month-to-month.

• For a well-insulated home using a smart electricity tariff, a heat pump can be cheaper to run while being significantly better for the environment.

The "cheaper" winner really depends on how you use it. But when you factor in the £7,500 grant, the lower maintenance, and the protection against potential rising gas levies, the heat pump is making a very strong case for itself.

We don’t have all the answers for every single house, as every home is a different situation. But we’re committed to being honest about what works and what doesn't. We aren't here to sell you a "fantastical vision"; we’re here to help you find the heating system that makes sense for your life and your budget.

Let’s keep the conversation going. We’re constantly updating our tech and our tariffs to make low-carbon living more affordable for everyone. It’s a journey we’re on together, one cosy radiator at a time.

Ready to see if your home is a heat pump hero? Get a quick heat pump quote, or dive deeper into our air source heat pump guides.

1. https://www.moneysupermarket.com/new-boiler/are-new-boilers-more-efficient/