Are heat pumps worth it in 2026? The running-cost case
A heat pump is the biggest single decision in decarbonising a home, and the one people fret over most, because the sticker price is high and the running-cost story sounds too good until you see the tariff behind it. The honest version: on a standard tariff an air-source heat pump runs close to level with a modern gas boiler; on a dedicated heat-pump tariff it is clearly cheaper; and the Boiler Upgrade Scheme grant brings the upfront cost within a few thousand pounds of a new boiler. This guide runs those numbers for a typical UK home and shows what tips the answer either way.
How a heat pump uses energy
A gas boiler burns fuel and turns roughly 90% of it into heat. An air-source heat pump does not make heat, it moves it, pulling warmth from the outside air and concentrating it. For every unit of electricity it draws, a well-designed system delivers about three to three-and-a-half units of heat. That ratio, measured across a whole year, is the Seasonal Coefficient of Performance (SCOP). A realistic SCOP on radiators is 3.2 to 3.6, and higher on underfloor heating.
That efficiency is why the sums work despite electricity costing several times more per unit than gas. The catch is that the gap between the two prices, and your SCOP, decide the whole result.
The running-cost maths
Take a typical home needing about 12,000 kWh of heat a year for heating and hot water. Here is the same heat delivered three ways, on mid-2026 prices.
| Setup | Energy used | Unit price | Annual running cost |
|---|---|---|---|
| Gas boiler (90% efficient) | ~13,300 kWh gas | ~6.5p | ~£865 |
| Heat pump, standard tariff | ~3,530 kWh electricity | ~26p | ~£920 |
| Heat pump, heat-pump tariff | ~3,530 kWh electricity | ~15p blended | ~£530 |
Read that table slowly, because it is the entire argument. On a standard tariff the heat pump lands a little above gas, near enough that the difference is noise. Move to a heat-pump tariff with a cheaper unit rate, and it drops well below gas, saving roughly £330 a year against the boiler. Against oil, LPG or direct electric heating, a heat pump is normally cheaper to run in every case, often by a wide margin.
The upfront cost, and the grant
A typical air-source heat pump install runs £8,000 to £14,000, with a common figure around £11,500 for a whole-home system fitted properly. That is the number that stops most people, and it is where the grant changes the picture.
The Boiler Upgrade Scheme in England and Wales pays £7,500 toward a heat pump, rising to £9,000 for off-gas homes replacing oil or LPG heating from 21 July 2026. Your installer applies for it and takes it straight off the quote, so you never handle the cash. Scotland runs its own grant and interest-free loan through Home Energy Scotland.
| Item | Typical figure |
|---|---|
| Air-source install (whole home) | ~£11,500 |
| Boiler Upgrade Scheme grant | minus £7,500 (or £9,000 for oil/LPG homes) |
| Net upfront cost | ~£4,000 (or ~£2,500) |
| A new gas boiler, for comparison | ~£3,000 |
After the grant, the net cost is close to what a new boiler would have cost anyway. That is the moment the question stops being "can I afford the jump?" and becomes "is my home ready for it?".
What decides whether it is worth it: design, not the badge
The single biggest driver of a heat pump's running cost is not the brand, it is how it is designed and run. A pump sized to a proper room-by-room heat-loss survey, running at a low flow temperature into large enough radiators or underfloor pipes, hits its rated SCOP and is cheap and comfortable. The same unit forced to run hot like a boiler, into undersized radiators, drops to a poor SCOP and costs more to run than it should. Three things move the answer:
- Insulate first. Lower heat demand lets the installer fit a smaller, cheaper pump and run it at a lower, more efficient flow temperature. Loft and cavity insulation done before the survey pays twice.
- Right-size the emitters. Bigger radiators or underfloor heating let the system deliver the same warmth at a lower flow temperature, which is where the efficiency lives.
- Choose an installer who commissions it. A pump left on factory defaults rarely performs. One that is balanced and tuned to your home is the difference between a 3.6 SCOP and a 2.8.
When a heat pump is worth it
- You heat with oil, LPG or electric storage heaters. A heat pump is almost always cheaper to run than these, so the case is strongest here, and the grant is larger for off-gas oil and LPG homes.
- You will move to a heat-pump tariff. The cheaper unit rate is what tips running costs clearly below gas.
- Your boiler is due for replacement. If you were about to spend £3,000 on a new boiler, the net cost of a heat pump after the grant is a small step up for a system that decarbonises your heating.
- You are insulating anyway, or already have. A reasonably insulated home lets the pump run efficiently and small.
When it is a harder call
- A newish, efficient gas boiler on mains gas, on a standard tariff. The running-cost saving is small, so the case rests more on carbon and future-proofing than on the bill.
- A poorly insulated home with no plan to improve it. High heat demand and small radiators force a low SCOP, which erodes the savings.
- No room for the outdoor unit or a hot-water cylinder. These are practical blockers worth checking before anything else.
None of these are permanent no's. They are reasons to insulate first, plan the emitters, and pick the right tariff, which is exactly the sequence set out in solar, heat pumps and EVs together.
The carbon case, briefly
Even on today's grid, a heat pump cuts the carbon of your heating sharply, because the electricity mix is far cleaner than burning gas at home, and it gets cleaner every year as more renewables come online. A gas boiler can only ever get worse relative to the grid. If lowering your home's emissions matters alongside the bill, the heat pump wins clearly, a point picked up in heat pumps explained.
Frequently asked questions
On a standard tariff an air-source heat pump runs close to level with a modern gas boiler. On a dedicated heat-pump tariff with a cheaper unit rate it is clearly cheaper, and against oil, LPG or electric heating it is cheaper in almost every case.
A whole-home install typically runs £8,000 to £14,000, often around £11,500. The Boiler Upgrade Scheme grant of £7,500 (or £9,000 for off-gas oil and LPG homes) brings the net cost close to that of a new boiler.
Yes, provided the system is designed for the home. Older houses usually need some insulation and larger radiators so the pump can run at a low, efficient flow temperature. Heat pumps work fine in cold weather; UK winters are mild compared with countries where they are standard.
Yes. It is a grant, not a loan, worth £7,500 or £9,000 depending on your current heating fuel, deducted from your quote by the installer. It is the main reason the upfront cost is now close to a new boiler.
A realistic seasonal figure is 3.2 to 3.6 on radiators, higher on underfloor heating, meaning roughly three-and-a-half units of heat per unit of electricity across the year. Good design and commissioning push it toward the top of that range.