Solar panel cost in the UK, from the government's own record

Not a quote. Not an estimate from someone who wants to sell you panels. What certified installations on existing homes actually cost, by system size, taken from the government's figures and rebuilt when they change. Nobody is going to ring you.

Most price guides give you one number, no date, and a form. This page gives you the official numbers, the date each was checked, and no form. Where we have done arithmetic of our own, it says so next to the figure.

Solar panel installation cost by system size

The government publishes the mean cost per kW for installations on existing homes, from its record of certified installs across Great Britain. New builds are counted separately, because a developer fitting panels to a whole estate is not paying what you will. We multiply the existing-homes rate by the system size. That is all.

Those four totals are our arithmetic from the DESNZ retrofit mean for existing homes, not published figures. Two things to read before you use them. The 5 kW total sits below the 4 kW one, and that is not a typo: the government's bands carry different rates, the bigger band is cheaper per kW, and five times the lower rate comes to less than four times the higher. It is the bands, not the market, which is why the rate sits beside each total. And the government publishes its bands as 0 to 4 kW and 4 to 10 kW without saying which side a system of exactly 4 kW falls on. We have put it in the smaller band. Treat that row as the top of the small-system range rather than a quote.

This is the figure for a house that already exists, which is the house most people reading this own. The government splits its home installations into existing homes and new builds, and new builds are fitted by developers at a lower rate per kW. Count the panels, the fitting and the grid connection, with VAT where any applies. No battery, no extended warranty. Almost exactly where it was the year before.

The middle band on existing homes, and the band more homes now fall into than any other. Bigger arrays cost less per kW than small ones, so a larger system is closer to reach than the small-band figure suggests. Same basis: panels, fitting and connection, no battery. Down on the year before.

Has the price fallen? Depends whose house

The government publishes three versions of the small-system rate, and they tell three different stories. On existing homes it did not move: £2,109.54/kW last year, £2,108.65/kW this year, under a pound apart. Across all homes, new builds included, it edged down, and the new builds are most of why. For homes and businesses together, the only series with three years of record, it has fallen two years running.

So a guide that says solar has got cheaper is not wrong. It is quoting a fall that a developer or a business saw and that a small system on an existing house did not. The middle band on existing homes is the honest good news: it fell from £1,748.31/kW to £1,651.40/kW.

Every home installation in the year, existing houses and new builds together, from the government's own record of certified installations rather than from anyone selling you one. It sits below the existing-homes figure because developers fit panels on new builds at a lower rate per kW. Same basis: panels, fitting and grid connection, with VAT where any applies, no battery or extended warranty. Down slightly on the year before, and the new builds are most of why.

The same government record, but counting business installations alongside homes. Businesses pay less per kW, so this figure sits below the homes-only one. If a price guide quotes a government per-kW figure without saying whether it is homes only, this is probably the one. The rate has fallen two years running.

Solar panels with a battery

None of the figures above include a battery. Two sources we trust publish a battery cost, and they measure different things, so we show both rather than picking the one that suits.

The gap between them is the size of battery being described, not a mistake by either. An average of everything fitted includes the large ones.

Three official-sounding numbers, three different rulers

You will see three solar costs quoted around the web, often against each other as if one must be wrong. None of them is. They measure differently.

• The government's figure is a cost per kW, split by system size, from certified installations on existing homes across Great Britain in the year. It counts the panels, the fitting and the grid connection, with VAT where any applies, and leaves out batteries and extended warranties. Multiply it by your system size and you get the table above.
• The MCS figure is the average price of a whole home installation, every size mixed together, for a calendar year.
• The Energy Saving Trust figure is a worked example for one typical system size, modelled rather than measured.

If a quote comes in above all three, the usual reasons are a battery, scaffolding on an awkward roof, or a bigger system than you were comparing against. If it comes in far below, ask what has been left out.

VAT on solar panels, while the zero rate lasts

What changes the price

No figures in this section, on purpose. Where an official source publishes one, it is elsewhere on this page with its receipt. Where none does, anyone who gives you a number is guessing. What the official data and the rules do support:

• System size. Bigger systems cost more in total and less per kW. The government's bands show it every year.
• Whether a battery is in the quote. The first thing to check when two quotes for the same roof differ.
• The roof. Scaffolding, roof type, how many faces the panels go on and how far the inverter sits from the consumer unit all move the labour.
• Where you live. The regional figures below show a real spread. London is dearest.
• New build or existing house. The table at the top is existing homes only. The government's record shows developers fit panels on new builds at a lower rate per kW, which is why the all-homes column in the table above sits lower.
• Timing. The VAT change above is the one date that moves every quote at once.

Solar panel cost by region

Where these figures come from

264,742 installations analysed in 2025/26. A record year, and two thirds of them were homes. Useful mostly as a reminder that this is now an ordinary thing people do, not a novelty. Every figure on this page carries its own receipt, with the source and the date we last checked it. When the government publishes the next year's data, this page is rebuilt from it.

Wondering what you can get towards it? The grants page covers what actually pays for panels, nation by nation, and what does not. Wondering how long it takes to earn its keep? The payback page gives the official figures and then does the sum with every input linked.

Questions people actually ask