A heat pump usually improves the carbon side of your Energy Performance Certificate (EPC), but it does not always improve the headline A to G band. That band is worked out from modelled running costs, and the calculation prices electricity well above gas. Replace oil, LPG or old electric heaters and the band often goes up. Replace a modern gas boiler in a draughty, poorly insulated house and the band can stay the same or slip by a few points.
On property value, UK studies link better EPC bands to higher sale prices, but the premiums are modest and none of the large studies isolates the heat pump itself. The clearer gains are for landlords facing the 2030 rental standard in England and Wales, and for sellers who can hand a buyer a complete, well-organised set of paperwork.
How Does an EPC Rate a Heat Pump?
An EPC rates a heat pump by modelling how much energy the home needs for space heating, hot water and lighting, then turning that into a standardised annual energy cost adjusted for floor area. That cost gives the SAP score from 1 to 100 and the A to G energy efficiency band shown at the top of the certificate. A second scale, the environmental impact rating, is based on modelled carbon dioxide emissions.
The assessor records the heat pump, the radiators or underfloor heating, the controls, the hot water cylinder and the fabric of the building. The software then applies standard assumptions for occupancy, heating hours and fuel prices. Your actual bills and the way you run the system play no part. Two identical houses with identical equipment get the same rating, whatever each household pays.
Which Version of RdSAP Is Used for EPCs in 2026?
EPCs for existing homes in 2026 are produced with RdSAP 10, which came into use from 15 June 2025. It is based on SAP 10.2 and made two changes that matter for heat pumps. The carbon factor for grid electricity dropped from around 0.5 kg to around 0.13 kg of CO2 per kWh, reflecting a cleaner grid. Heat pumps also now appear as recommendations on the certificate where a home suits one.
Why Can a Heat Pump Lower Your EPC Band?
A heat pump can lower your EPC band because the energy efficiency rating is a cost rating, and the unit price the calculation uses for electricity is well above the price it uses for mains gas. A heat pump turns each kWh of electricity into several kWh of heat over a year (the government-funded Electrification of Heat trial found a median of about 2.8), but if the fuel price gap in the model is wider than that efficiency gain, the modelled bill barely moves or goes up.
The Energy Saving Trust states plainly that homes with electric heating, including heat pumps, sometimes get a lower EPC rating than similar homes heated by gas or oil. It also points out that the carbon figure on the same certificate often tells a different story. The government has accepted the problem. Its January 2026 response on privately rented homes says the new EPC metrics will resolve the issue of consumers being penalised for installing low carbon heating such as heat pumps.
The effect is strongest in homes with high heat loss, because the larger the heating demand, the more the fuel price assumption dominates the result. A well-insulated home with a heat pump designed for a low flow temperature is far less likely to see a drop.
How Much Will My EPC Band Change After Installing a Heat Pump?
There is no fixed answer, because the change depends mostly on what the heat pump replaces and how much heat the house loses. We have not found a large published dataset of before and after EPCs for heat pump installs, so treat the table below as the typical direction of travel under the current rating rather than a promise.
| System replaced | Energy efficiency band (A to G) | Environmental impact (carbon) rating |
|---|---|---|
| Modern gas combi or system boiler | Often similar; can fall a few points in poorly insulated homes | Usually improves |
| Oil boiler | Often similar or better | Usually improves |
| LPG boiler | Often better | Usually improves |
| Electric storage heaters or panel heaters | Usually better, because far less electricity is needed for the same heat | Usually improves |
| Solid fuel or old back boiler | Usually better | Usually improves |
Bands are also narrow. Band C starts at a SAP score of 69, so a home scoring 70 drops to D if it loses just two points. Small modelling changes can move a certificate across a band line in either direction, which is why insulation work alongside a heat pump often makes the difference.
What Is Changing With EPCs and the Home Energy Model?
New-style EPCs with four headline metrics are coming, but the launch has been pushed back to the second half of 2027. The government first aimed for October 2026, then confirmed the delay in March 2026. Until then, the current A to G certificate produced under RdSAP 10 remains the one that counts for sales, lettings and lenders.
The reformed certificates will be based on the Home Energy Model (HEM), which replaces SAP. HEM calculates heat pump performance at each time step under the conditions at that moment, rather than applying one seasonal figure. The four headline metrics confirmed in the government response are shown below.
| New EPC metric | What it measures | Likely effect of a heat pump |
|---|---|---|
| Energy cost | Modelled cost of running the home | Depends on fuel prices and heat loss, as now |
| Fabric performance | How well walls, roof, floors and windows keep heat in | None; insulation drives this |
| Heating system | Efficiency and carbon impact of the heating system | Strongly positive |
| Smart readiness | Ability to shift energy use, for example with smart controls or batteries | Positive where controls and tariffs allow load shifting |
Secondary metrics for energy demand and carbon will sit alongside these. Certificates will stay valid for 10 years, and existing EPCs keep their 10-year validity. Scotland runs its own EPC regime and has also delayed its reforms, with the current system staying in place until further notice.
Does a Heat Pump Help Landlords Meet EPC C by 2030?
Yes, a heat pump will count towards the new standard for privately rented homes in England and Wales, but it cannot do the job alone. The government confirmed on 21 January 2026 that all private tenancies must comply by 1 October 2030. Landlords must first meet a fabric performance standard, then meet either a heating system standard or a smart readiness standard. A heat pump sits in the heating system part.
| Rule (England and Wales) | Current position |
|---|---|
| Compliance deadline | 1 October 2030 for all tenancies |
| Primary standard | Fabric performance, met first |
| Secondary standard | Heating system or smart readiness, landlord’s choice |
| Cost cap | £10,000 per property, or 10% of the property’s value if lower |
| Existing EPC C | An EPC C (energy efficiency rating) obtained before 1 October 2029 stays compliant until it expires |
| Maximum penalty | £30,000 per property per breach |
| Legal status | Policy confirmed; new powers and regulations still to be made |
The fabric-first order matters. A landlord who fits a heat pump in an uninsulated house has not met the primary standard, so insulation still has to be tackled. The cautious plan is to do fabric work first, then size the heat pump to the lower heat loss, which also keeps it smaller and cheaper to buy and run.
In Scotland, the Scottish Government has proposed its own standard based on a reformed EPC heat retention rating of band C, applying to new tenancies from 2028 and all private lets by the end of 2033. That was still a proposal when we last checked, and it depends on the reformed Scottish EPC, so check the latest position before planning work. The England and Wales rules do not apply in Northern Ireland.
Do Green Mortgages Reward Heat Pumps?
Green mortgages reward a heat pump only indirectly, because most lenders price them on the EPC band or SAP score rather than on the heating system. A heat pump that lifts a home into band A or B, or past a lender’s SAP score threshold, can unlock a cheaper rate or cashback. One that leaves the band unchanged usually earns nothing extra.
As of September 2026, examples include green rates for homes rated A or B at some high street lenders, cashback linked to SAP scores at Nationwide, and products at smaller lenders such as Kensington and Saffron that reward an EPC improvement made after completion. Terms change often, so check with a broker. For most owners the bigger financial effect of a heat pump is on running costs and grants, not on mortgage pricing.
Does a Heat Pump Add Value to Your Home?
A heat pump may add some value through a better EPC band, but UK evidence shows a modest premium for efficiency and does not measure the heat pump on its own. The main studies are summarised below.
| Study | Date | Finding |
|---|---|---|
| Nationwide | June 2026 | Homes rated A or B sold for about 1.6% more than similar D-rated homes (around £4,500); F or G homes sold for about 1.4% less |
| Rightmove | August 2023 | Homes that improved from D to C gained about 3% more than local price growth; E to C about 7%; F to C about 15% |
| Department of Energy and Climate Change | June 2013 | Band A or B homes averaged 14% more than band G homes, rising to 38% in the North East |
Read these carefully. Rightmove’s figures come from homes that sold twice with different EPCs, so the uplift may also reflect other improvements made between sales. The 2013 government study used sales from 1995 to 2011 and did not account for property condition. Nationwide’s more recent figure is the smallest. The fair reading is that moving up a band or two can help, and that moving from the bottom bands helps most.
So if a heat pump lifts your EPC band, some value may follow. If it only improves the carbon rating, expect the benefit to show up in buyer interest and lower bills rather than as a line on a valuation.
What Will Buyers Ask For When a House Has a Heat Pump?
Buyers and their conveyancers will usually ask for the MCS certificate first, followed by warranty and servicing records. A heat pump with a full paper trail is much easier to sell than one where nobody can say who fitted it or how it was designed. The documents below are the ones worth keeping together.
| Document | Why buyers want it |
|---|---|
| MCS certificate | Shows the system was installed by a certified installer to MCS standards; usually the first thing a buyer’s conveyancer asks for |
| Design and heat loss summary | MCS installers must give customers the room heat losses, emitter details and design flow temperature, which shows the system was sized properly |
| Manufacturer warranty and registration | Confirms the length of cover, whether it transfers to a new owner, and any servicing conditions |
| Service history | Proves any servicing conditions of the warranty have been met |
| Workmanship guarantee | Covers the installation itself, separate from the product |
| Commissioning records and controls manual | Helps the new owner run the system at the flow temperature it was designed for |
If you have lost the MCS certificate, the system owner can request a copy from MCS with proof of address. Do this before you list the house, not when the conveyancer’s enquiries arrive. Buyers who have never lived with a heat pump may also ask about running costs, so a year of meter readings or bills is useful to have to hand.
How Can You Get the Best EPC Result From a Heat Pump?
You get the best EPC result by cutting heat loss before or alongside the heat pump and by making sure the assessor records the system correctly. Loft and cavity wall insulation, draught-proofing and better glazing all raise the SAP score directly, and they reduce the heating demand that the fuel price assumption acts on.
- Give the assessor the MCS certificate, the product details and the design paperwork so the heat pump, cylinder and controls are recorded accurately.
- Make sure the cylinder insulation, heating controls and any thermostatic radiator valves or zoning are visible and working on the day.
- If you have solar panels or a battery, have the details ready, as these affect the rating too.
- Get a new EPC after the work. An old certificate stays valid for 10 years and will still show the previous heating system.
If you are weighing up a heat pump partly for the EPC, ask your installer to explain how the design flow temperature and your insulation plans will affect running costs, then decide on the evidence for your house. Our engineers can survey your home and give you a room-by-room design and a clear quote.
