The short answer
For most UK homes replacing a heating system that has reached the end of its life, yes. For homes with a working boiler and no immediate need to replace it, usually not yet. And for a small number of properties, no, at least not until other work is done first.
That is a less satisfying answer than either side of this argument tends to give, but the honest version depends on three things: what you are replacing, what your property is like, and what electricity tariff you are willing to move to. This page works through all three with current numbers. If you want the installation figures first, see what a heat pump actually costs.
The running cost question, with actual arithmetic
Almost every claim you will read about heat pump running costs is either “they cost more than gas” or “they cost less than gas”, and both are stated as though the answer were fixed. It is not. It turns on one number, and you can work it out yourself.
Under the current price cap, running from 1 October to 31 December 2026, a typical direct debit customer in England, Scotland or Wales pays around 26.32p per kWh for electricity and 7.97p per kWh for gas.
A gas boiler is not 100% efficient. A reasonable working figure for a typical UK domestic boiler is around 85%. So the real cost of a unit of heat from a gas boiler is 7.97 divided by 0.85, which is about 9.4p per kWh of heat.
A heat pump’s equivalent number depends on its seasonal efficiency, usually quoted as SCOP. Divide the electricity price by the SCOP:
| Heating system | Cost per kWh of heat |
|---|---|
| Gas boiler at 85% efficiency | 9.4p |
| Heat pump at SCOP 2.5 | 10.5p |
| Heat pump at SCOP 3.0 | 8.8p |
| Heat pump at SCOP 3.5 | 7.5p |
| Heat pump at SCOP 4.0 | 6.6p |
| Heating oil | 12.0p to 12.8p |
Which gives you the number that actually matters. On the standard price cap, a heat pump needs a real-world SCOP of about 2.8 to break even with a gas boiler. Below that it costs more to run. Above it, it costs less, and the gap widens quickly.
Is 2.8 achievable? Comfortably, on a well-designed system. Octopus reports a real-world seasonal figure of around 3.6 across its installed fleet, and individual owners publishing their own data typically report somewhere between 3.2 and 3.5 over a full year. The Boiler Upgrade Scheme itself requires a minimum SCOP of 2.8 for eligibility, which is not a coincidence.
But that is the real-world figure, not the brochure figure. A system that is oversized, badly commissioned, or running at a high flow temperature because the radiators were never upgraded will land well below its rated performance. This is the single biggest variable in whether a heat pump saves you money, and it is determined almost entirely by the quality of the installation rather than the brand of the box.
Three things those numbers leave out
Standing charges. If you remove your gas supply entirely, you stop paying the gas standing charge, currently around 30p a day, which is roughly £108 a year before you use any energy at all. That is a genuine saving, but only if you disconnect the supply rather than leaving it capped for a gas hob.
The VAT position is temporary and flattering. The government has removed VAT from household electricity from 1 October 2026 to 31 March 2027. That is why electricity has held roughly flat this quarter while gas rose nearly 9%. It makes the heat pump case look better than it structurally is. If VAT returns to 5% in April 2027, electricity goes back to around 27.6p and the break-even SCOP rises to roughly 2.95. Still achievable, but a smaller margin. Anyone quoting you savings based on this winter’s rates is quoting you a temporary number.
Smart tariffs change the picture again. Heat pump tariffs such as Cosy Octopus offer several cheaper windows each day, and a heat pump paired with a hot water cylinder can shift a good deal of its load into them. That can move running costs meaningfully below the table above. It also means committing to a specific supplier and tariff, and tariff terms change. Treat it as upside rather than as the baseline.
The upfront cost question, which is the real one
Here is where most “is it worth it” articles quietly cheat. They compare running costs, find a saving, and present a payback period against the installation cost.
The problem is that the saving is usually small. If your heat pump runs at SCOP 3.2 and you were previously on gas, you are saving in the region of 1p per kWh of heat. On a home using 10,000 kWh of heat a year, that is roughly £100, plus £108 if you removed the gas supply. Against a net installation cost that could be anywhere from a few hundred pounds to £7,500 after the grant, a payback calculation gives you anything from two years to never.
So the running cost saving is not the case for a heat pump in a gas-heated home. It is a rounding error either side of neutral.
The actual case is a replacement comparison. If your boiler has failed or is close to it, you are not choosing between a heat pump and nothing. You are choosing between a heat pump and a new boiler. A new gas boiler installed is commonly £2,000 to £3,500. A heat pump after the £7,500 grant frequently lands in a similar range, sometimes lower, sometimes considerably higher depending on your property. At that point the decision is about which system you want for the next fifteen years, not about payback.
When a heat pump is genuinely worth it
- You are off the gas grid on oil or LPG. This is the strongest case by a distance. Oil delivers heat at around 12.0p to 12.8p per kWh against roughly 8p for a decent heat pump, the price is volatile in a way the electricity cap is not, and the grant is currently £9,000 rather than £7,500 until March 2027.
- Your boiler is at or near the end of its life. The comparison becomes heat pump against new boiler, which is a fair fight.
- Your home is reasonably insulated and has space for a cylinder. Both push the SCOP up and the installation cost down. We work through how this plays out in a 1930s semi, a Victorian terrace, a bungalow and a flat.
- You are willing to move to a heat pump tariff and let the system run steadily. A heat pump rewards being left alone and punishes being treated like a boiler.
- You are already renovating. Radiator upgrades and pipework are far cheaper when the floors are up anyway.
When it is not worth it
Your gas boiler is three years old and working. There is no financial case for replacing it now. The grant runs to 2030, so it will very probably still be there when the boiler fails. Doing nothing is a legitimate decision and here it is the right one.
Your home is poorly insulated and you cannot afford to address it. A heat pump will still heat the house, but it will need to be larger, cost more to install, run at a higher flow temperature and therefore a lower SCOP, and you will end up on the wrong side of that break-even number. Fabric first is a cliché because it is true. Loft and cavity insulation are cheap by comparison and improve any heating system.
You have nowhere sensible for a hot water cylinder. Combi boiler households often have no airing cupboard, and finding a cubic metre of space is sometimes genuinely impossible. Air-to-air heat pumps sidestep this but provide no hot water at all, so you need another answer.
You are moving within two or three years. The evidence that a heat pump is recovered in sale price is thin. If you will not be there to use it, the case is environmental rather than financial, which is a perfectly good reason but a different one.
You want to keep the gas boiler as a backup. Hybrid systems are not eligible for the grant, and the heat pump must fully replace the existing system. This rules out a common instinct among cautious households.
Questions worth asking before you commit
If you do get quotes, these four questions separate a good installer from a bad one faster than anything else:
- What flow temperature is this system designed around? Lower is better for efficiency. A design at 55°C with no radiator changes usually means nobody did the heat loss calculation properly.
- What SCOP should I expect in practice, not on the datasheet? An installer who will not put a realistic figure in writing is telling you something.
- Which radiators are you changing and why? “None” is occasionally correct and usually a warning sign.
- What is the price before the grant? Compare quotes on the pre-grant figure. It is the only number that tells you what the work is actually being priced at.
For MCS certification, comparing quotes and the rest of the checks, see our guide to choosing a heat pump installer.
Frequently asked questions
The questions below come up most often once people have got past the headline claims on either side.
Do heat pumps work in cold weather in the UK?
Yes. Efficiency falls as the outside temperature drops, which is why the seasonal figure matters more than the peak one, but a correctly sized system heats a UK home through a normal winter. The homes that struggle in January are generally ones where the system was undersized or the heat loss calculation was wrong.
Will a heat pump cut my energy bills?
If you are replacing oil or LPG, very likely and by a meaningful margin. If you are replacing mains gas, expect roughly break-even, with the direction depending on your system’s real-world efficiency and your tariff. Anyone promising large savings on a gas-to-heat-pump switch is selling rather than calculating.
Do I need to replace all my radiators?
Usually some, rarely all. Heat pumps run at lower flow temperatures, so radiators need more surface area to deliver the same heat. A proper room-by-room heat loss survey tells you which ones, and any installer skipping that survey is guessing.
Does a heat pump add value to my home?
There is no reliable evidence that it is recovered in sale price at present. It does typically improve an EPC rating by one to three bands, which matters more for landlords facing minimum standards than for owner-occupiers.
Are heat pumps noisy?
Modern units sit at roughly the level of a fridge at a few metres. Siting matters more than the specification: against a neighbour’s bedroom wall is a poor choice regardless of the decibel rating.
How long do they last?
A typical expectation is 15 to 20 years, broadly comparable to a gas boiler, with annual servicing. The hot water cylinder will usually outlast the heat pump itself.
Last updated 15 October 2026. Energy prices taken from the Ofgem price cap for 1 October to 31 December 2026. Grant values verified against Ofgem’s scheme guidance. Energy prices change quarterly and the electricity VAT reduction is due to end on 31 March 2027, so check the date above before relying on the figures here. Written by Ben Jardine.