How much do solar panels cost in the UK?
"How much will it cost?" is the second question after "is it worth it?", and it's where a lot of online figures fall down. The honest answer is a range, because the price tracks how many panels you fit, whether you add a battery, and how awkward your roof is to work on. Here are the actual numbers behind that range.
The headline numbers
Solar is usually priced per kWp of capacity, and the rate falls as the system grows, because the fixed costs of scaffolding, design and a day's labour are spread over more panels. A small install runs roughly £1,400 to £1,800 per kWp; a larger one can drop nearer £1,000. In whole-system terms for panels only, that puts a typical home in this sort of territory:
- A 3 kWp system (about 7 panels): roughly £5,000 to £6,500.
- A 4 kWp system (about 9 panels): roughly £6,000 to £8,000.
- A 5 to 6 kWp system (12 or more panels): roughly £7,500 to £10,000.
Those are panels, inverter, mounting, wiring, scaffolding and certification, with the install done by an MCS-certified firm. They're a starting point, not a quote: your roof, region and installer move them. For a figure tied to your actual home, the calculator gives a cost range in a couple of minutes.
What a battery adds
A battery is usually the single biggest line item, and it's priced per usable kWh, roughly £350 to £600 installed depending on brand and chemistry. A 5 kWh pack adds around £2,000; a 10 kWh one £4,000 or more. That can lift a £7,000 panels-only job to £9,000 to £12,000 all in. Whether it earns that back depends entirely on how and when you use electricity, which is its own decision: see do I need a battery.
The 0% VAT window
One real saving applies right now. Domestic solar and battery installations carry 0% VAT in the UK until 31 March 2027, down from 5% before and the 20% on most goods. On a £9,000 install, the old 5% rate would have added about £450, so the timing genuinely matters. After March 2027 the rate is set to return to 5%.
The costs quotes often leave out
The headline price isn't the whole 25-year cost. A string inverter typically lasts 10 to 15 years, so most systems need one replacement over their life, often £800 to £1,500. Steep, high or multi-face roofs need more scaffolding and labour, and integrated or in-roof mounting costs more than on-roof rails. Bird or pigeon proofing around the array is a common £200 to £400 add-on that rarely appears in the first quote.
How to sanity-check a quote
- Compare on £ per kWp, not the headline total; it's the only way to line up different system sizes.
- Check the panel and inverter brands and warranties (good panels carry 25-year output warranties), and that the installer is MCS-certified, which you need for SEG export payments.
- Make sure the quote states the system size in kWp, the expected annual generation in kWh, and any battery capacity. A quote with no generation estimate is a quote you can't compare.
- Get two or three quotes. Installer-to-installer variation on the same roof is wide, and it's the cheapest lever you have.