| Median, 0-4 kW installs (DESNZ, 2025/26, DNC basis) | £1,780.25 per kW |
|---|---|
| Median, 4-10 kW installs (DESNZ, 2025/26, DNC basis) | £1,696.97 per kW |
| Median, 10-50 kW installs (DESNZ, 2025/26, DNC basis) | £1,262.17 per kW |
| Installs in the 2025/26 analysis | 265,682 on the DNC basis (Great Britain, MCS data) |
| Energy Saving Trust typical system | About 4.5 kWp for around £7,600 (page updated 27 August 2026) |
What the official data says
The Department for Energy Security and Net Zero (DESNZ) publishes real installation costs every year. The latest release came out on 28 May 2026 and covers April 2025 to March 2026. It uses Microgeneration Certification Scheme (MCS) records for Great Britain.
On the DNC basis, DESNZ counted 265,682 installations in that year. That is a record, and it is 28 per cent more than the year before. On the TIC basis, by contrast, the count is 264,742. After adjusting for inflation, DESNZ says the median cost per kW fell for every size band. It puts that down to more supply and better technology.
Here are the 2025/26 medians, exactly as published. DESNZ gives them in pounds per kW, split by system size.
| System size | Median, DNC basis | Median, TIC basis |
|---|---|---|
| 0-4 kW | £1,780.25 per kW | £1,595.06 per kW |
| 4-10 kW | £1,696.97 per kW | £1,545.89 per kW |
| 10-50 kW | £1,262.17 per kW | £1,203.85 per kW |
Source: DESNZ, Solar PV cost data, 2025/26 installs, published 28 May 2026. The median is the middle price. In other words, half of installs cost less per kW and half cost more.
DNC or TIC, which should you use?
DESNZ publishes the data two ways. Declared net capacity (DNC) is the most a system can export to the grid. Total installed capacity (TIC) is the most it can generate. DESNZ says TIC is usually higher. As a result, the cost per kW on that basis is lower.
Your quote lists kWp, which describes the panel array. So the TIC column is the closer match for most quotes. That is our reading, not DESNZ advice.
Cross-check with a second source
Energy Saving Trust says a typical home system is around 4.5 kWp and costs around £7,600. Its page was last updated on 27 August 2026.
We can test that against the official data with simple arithmetic. These sums are our own working, not figures from either source.
- 4.5 kW at the 4-10 kW TIC median: 4.5 x £1,545.89 = £6,956.51
- 4.5 kW at the 4-10 kW DNC median: 4.5 x £1,696.97 = £7,636.37
The Energy Saving Trust figure sits very close to the DNC result. It is also within about 10 per cent of the TIC result. Therefore the two sources broadly agree for a typical home. Even so, prices vary, so get written quotes.
Worked illustrations
These examples multiply a sourced median by a system size. They are arithmetic, not prices anyone will quote you. For example, the 4 kWp line is simply 4 x £1,595.06.
| System size | Median used (TIC, 2025/26) | Arithmetic result |
|---|---|---|
| 3 kWp | £1,595.06 per kW | £4,785.18 |
| 4 kWp | £1,595.06 per kW | £6,380.24 |
| 6 kWp | £1,545.89 per kW | £9,275.34 |
A bigger system costs more in total but less per kW. DESNZ notes that the median cost per kW of a 10-50 kW install is about a third lower than a 0-4 kW install on the DNC basis.
What moves a price
A median hides a wide range, because several things push your quote above or below it.
- Scaffolding. Most roof jobs need it. Energy Saving Trust says you can cut costs if scaffolding is already up for roof repairs. Our guide to what scaffolding adds to a solar quote shows how to spot it as a line item.
- Roof and access. Energy Saving Trust lists difficult roof access and any need to renew the roof covering. Likewise, Which? adds structural upgrades and a challenging roof layout.
- Inverter and optimisers. Which? names inverter quality as a cost driver. Our comparison of string inverters, microinverters and optimisers explains the trade-offs.
- System size. More panels cost more overall, as the table shows. Our guide on how many panels you need helps you size it before you ask for prices.
- Battery. DESNZ leaves batteries out of its figures. So never compare a quote with a battery against the table. See our solar battery cost guide.
- Extras. Which? also lists electrical upgrades and monitoring. In addition, add-ons such as bird-proofing can appear as separate lines.
Where you live matters a little
DESNZ also publishes regional figures. These are means, not medians, so do not compare them with the table above. For 0-4 kW installs in 2025/26 on the DNC basis, the mean was £2,008.32 per kW across Great Britain.
By comparison, London’s mean was £2,176.96 per kW and the South East’s was £2,081.53 per kW. The North East’s was £1,878.20 per kW. If you live in the capital, see what installers in London charge. Homeowners nearby can read about typical quotes across the South East.
How to read your own quote against it
Follow these steps with a quote in front of you.
- Find the total price and the kWp of the panels.
- Take off any battery, EV charger or other extra, because DESNZ excludes them.
- Divide the remaining price by the kWp. That gives your price per kW.
- Compare it with the right row in the table.
- Check what is included: scaffolding, grid application, MCS certificate and warranty.
Then ask why any gap exists. A price above the median is not wrong if your roof is hard to reach. However, a price far below it deserves a closer look at the parts list.
DESNZ costs include VAT where it applies. Residential installs currently qualify for 0% VAT until 31 March 2027, so read the VAT and grants guide before you compare with older prices.
Also, our free quote checker does this division for you in your browser. If you hold several quotes, compare solar quotes side by side using the same method.
Why the numbers can change
DESNZ revised its 2023/24 and 2024/25 figures after it received more complete MCS data. As a result, older articles may quote different numbers. DESNZ plans its next publication for 27 May 2027.
Prices also move with the market, because supply and demand drive them. For that reason, always ask for a dated, written quote. Treat any table, including this one, as a starting point.