Good Houses
Heat pump cost calculator
Step 1 of 3
Where's the property?
A postcode gives you figures for your actual area, and tells us which grant scheme applies. You can also skip this and get a regional estimate with no grant applied.
A heat pump is not a like-for-like swap for a gas boiler, and whether it suits your house is a bigger question than what it costs.
It works in a house with reasonably good insulation, manageable heat loss, and radiators able to keep rooms warm at lower water temperatures than a boiler runs at. You also need room for the outdoor unit, a hot water cylinder and the pipework between them. The house does not have to be perfect, but it does have to stay comfortable without the high flow temperatures a boiler relies on.
If that does not describe your house, a heat pump will not perform the way it is sold to you, and the answer is that it is not suitable yet.
The figure above already accounts for the grant: the Boiler Upgrade Scheme in England and Wales, or the Home Energy Scotland Grant and Loan in Scotland. Higher rates exist in both, for off-grid properties replacing oil or LPG in England and Wales, and for rural and island properties in Scotland.
How sizing sets the price
Sizing comes first, because everything else follows from it. The calculator estimates how much heat your home loses, from its floor area and its EPC rating, and converts that into the pump size you would need. If you do not know your floor area we estimate it from property type and bedrooms; if you do not know your EPC rating you can say so, and a mid-range assumption is used rather than a flattering one.
That size then drives the cost: the pump itself, a hot water cylinder, the radiators that need upgrading, pipework and controls, the survey and design, and installation labour adjusted for your area. Radiator upgrades are estimated from the age of your existing radiators and your EPC band, because an older, poorly-insulated house needs far more of them changed than a new one.
Any grant you qualify for is then deducted, and the figure shown is what you would actually pay. The grant value and eligibility are maintained as settings rather than written into the page, because schemes change.
Running cost is calculated separately, and compared against what you are burning now: annual heat demand divided by a seasonal efficiency figure that varies with how well insulated your home is, priced at current energy rates.
The result is always a range, never a single figure. A precise number would be a false promise, because two builders quoting the same job honestly can land a long way apart. Everything is rounded rather than shown to the pound, for the same reason.
Every figure behind this comes from a table we maintain by hand and review on a schedule. The date of the last review is shown on this page, so you can judge how current it is rather than take our word for it.
What the heat pump figure covers
The figure covers:
- The heat pump, sized to your home rather than to a standard package
- A hot water cylinder, unless you have said there is nowhere to put one
- Radiator upgrades, estimated from your radiator age and EPC band
- Pipework and controls
- Survey and system design
- Installation labour, adjusted for your area
- Any grant you qualify for, deducted from the total
What the heat pump figure leaves out
Not in the figure:
- Insulation work, which is often the thing that has to happen first
- Upgrading your electrical supply if the incoming supply cannot carry the pump
- Building or clearing a base and running space for the outdoor unit
- Planning permission where the unit affects a listed building or conservation area
- Removing the old boiler and capping the gas supply
- Redecorating where radiators change size or position
If your EPC is E or below the calculator flags insulation as a prerequisite rather than a suggestion. A heat pump in a poorly insulated house is an expensive way to be cold.
Why heat pump installation costs more in some regions
Labour is the part of a heat pump installation that moves most by region, so it is the part we adjust. Every area carries a labour multiplier, and the calculator applies it to the labour element rather than to the whole figure, because materials cost broadly the same everywhere, and scaling them by region would overstate the difference.
Where we hold published data for your area, that area's own multiplier is used. Where we do not, the calculator falls back to the figure for your region and the page says so. It will never quietly borrow a nearby city's numbers and present them as local. A London figure on a Cumbrian postcode is worse than no figure at all.
Taking this to heat pump installers
Take it to real quotes, and treat it as the shape of the answer rather than the answer. Get three written quotes from MCS-certified installers, since certification is usually required for the grant, and compare what each one includes before you compare the totals, because the cheapest number on the page is often the one leaving the most out.
If a quote comes in below our range, that usually means a newer business building a reputation, or work that cuts corners. Above it usually means limited local supply, or a firm with higher overheads. Both can be the right choice. The question worth asking is what is included, not why the number differs.
Worth asking every firm you speak to:
- What heat loss survey are you doing, and will I get the calculations?
- What size have you specified, and why that size?
- How many radiators are you changing, and which?
- What SCOP are you predicting for my house, not in general?
- Are you handling the grant application?
Common questions
Do I need to know my EPC rating?
No. There is an "I don't know" option and the calculator uses a mid-range assumption. But finding it is worth five minutes: the government holds a free public register you can search by postcode, and the estimate gets considerably more useful with the real figure.
Will it actually be cheaper to run than my boiler?
Sometimes, and the calculator shows both rather than assuming the answer. It depends on your insulation, the electricity and gas prices at the time, and how efficiently the pump runs in your house. In a poorly insulated home the answer is often no, not until the insulation is done.
Why does it want to change my radiators?
A heat pump runs at a lower flow temperature than a gas boiler, so radiators sized for a boiler are often too small to deliver the same heat. Older radiators and poorer insulation both mean more of them need changing.
Is this a quote?
No. It is an estimate built from typical costs, and no contractor is bound by it. Use it to know whether a quote you have been given is roughly where it should be, and to walk into that conversation knowing what questions to ask.
Why do you show a range instead of one number?
Because one number would be misleading. The answer to "what will this cost" is a range, and where you land inside it depends on your property, your area and who you hire. Any tool giving you a single figure to the pound is telling you something it cannot know.
Do you save what I type in?
No. The calculation runs and the answers are discarded. Nothing is written down unless you explicitly ask us to email or save a result. We do not build a profile from calculator use.
How current are the figures?
The date of the last review is shown on this page. The costs behind the calculator are maintained by hand rather than scraped, and reviewed on a schedule.