10kWh battery price: what a mid-size home battery costs
The 6 to 11 kWh band is where prices per kWh settle down, and where the official median barely moved in a year. This page prices the sizes in it and explains what moves a quote up or down.
Quick answer
A 10 kWh home battery costs about £8,800 fitted, modelled from DESNZ's 2025/26 median of £890 per nominal kWh for batteries of 6 to 11 kWh, at 0% VAT (to 31 March 2027). From 1 April 2027, when VAT on installed batteries becomes 5%, the same job would be about £9,200.
Where 10 kWh sits on the price line
The band's average battery in 2025/26 was 9.8 kWh, almost exactly the size most people mean when they say "a 10 kWh battery". That is why the modelled price and the simple sum agree so closely here: about £8,800 on our line, £8,900 if you multiply by £890.
Move to either end of the band and they drift apart. Near 6 kWh the line still carries some of the small band's higher cost per kWh; near 11 kWh it is already leaning towards the large band's £630. The methodology page shows how the line is drawn and why we prefer it to multiplying.
Prices for 6 to 10.5 kWh batteries
| Nominal size | 0% VAT (to 31 March 2027) | 5% VAT (from 1 April 2027) | Per nominal kWh |
|---|---|---|---|
| 6 kWh | about £7,100 | about £7,400 | £1,176 |
| 7 kWh | about £7,500 | about £7,900 | £1,071 |
| 8 kWh | about £7,900 | about £8,300 | £992 |
| 9 kWh | about £8,400 | about £8,800 | £930 |
| 9.5 kWh | about £8,600 | about £9,000 | £904 |
| 10 kWh | about £8,800 | about £9,200 | £876 |
| 10.5 kWh | about £8,800 | about £9,300 | £843 |
Read the last column from top to bottom and the price per kWh falls steadily, from about £1,180 at 6 kWh to about £840 at 10.5 kWh. A few extra kWh in this band add relatively little to the total, which is one reason it is so popular. That does not make a larger battery the better buy: stored energy you never use is still paid for.
A steady band in a growing market
DESNZ recorded 14,457 batteries in this band in its 2025/26 sample, up from 8,476 the year before, yet the median price per kWh slipped from £910 to £890. The mean moved the same way, from £890 to £870. In plain terms: far more households bought a mid-size battery and the middle price did not rise.
One detail is worth noticing. In 2025/26 the band's mean (£870) sat below its median (£890). A mean lower than the median usually means a tail of cheaper installs pulling the average down rather than a few very expensive ones pushing it up. It is a statistical reading, not a promise: DESNZ does not publish the spread, so we can't say how wide that tail is.
What the figures don't cover matters as much as what they do. They count batteries registered with MCS in existing homes only, priced with fitting and connection but without panels, extended warranties or other building work. A 10 kWh battery bundled with new panels is a different sum; see solar and battery prices for how to split one.
What pushes a 10 kWh quote above the median
Two households can both be quoted for 10 kWh and see very different totals. These are the usual reasons, none of which DESNZ prices separately:
- A new inverter. If the battery can't connect to the solar inverter you already have, the quote may add a separate battery inverter, or swap the old one for a hybrid unit that handles both.
- Backup for power cuts. Keeping some circuits running when the grid fails needs switching equipment and set-up time.
- Where the battery has to go. Fire-resisting separation, ventilation to outdoors, an interlinked alarm or impact protection in a garage all add work.
- The network application. Storage over 3.68 kW of inverter power needs a G99 application before installation, according to MCS. Ask which route your quote assumes: a battery paired with an inverter above that line takes the longer one.
- Usable capacity. A battery that lets you use more of its label size can justify a higher price, and one that lets you use less can make a lower price look better than it is.
Our page on what adds to a battery quote treats each as a line item, and the quote checker tells you how far any total sits from £890 per kWh.
Sizing a mid-size battery against your own use
Ofgem's typical consumption values changed on 1 July 2026. A medium-use home on a single-rate meter now uses 2,500 kWh a year, about 6.8 kWh a day; on a multi-rate meter the medium figure is 3,400 kWh, about 9.3 kWh a day. A battery in this band can cover much of an evening and night for a typical home, but only if there is solar or cheap-rate power to fill it, which in winter there often isn't.
We keep sizing to a single question on this site, because how a battery fills and empties through the seasons is a subject in itself. The practical point for price is simple: work out which of your evening and overnight use you want to cover, price the usable size that covers it, and check how much you are paying for each kWh beyond that. If you are near the 11 kWh line, the large battery price page shows where the next band starts; if you are below 6 kWh, compare with the 5 kWh battery price.
10 kWh battery price questions
How much does a 10 kWh battery cost to install?
About £8,800 at 0% VAT (to 31 March 2027), modelled from DESNZ's 2025/26 figures, or £8,900 if you simply multiply 10 kWh by the band's £890 median. Invoiced from 1 April 2027, the modelled figure becomes about £9,200.
Why is a 10 kWh battery not twice the price of a 5 kWh one?
Because a large part of any installation costs the same whatever the size. The official medians fall from £1,300 per kWh under 6 kWh to £890 between 6 and 11 kWh, so doubling the size from 5 to 10 kWh adds roughly a third to the modelled price (about £6,500 to about £8,800).
Is a 10 kWh quote over £10,000 too high?
Not necessarily. Half of the batteries DESNZ recorded in this band cost more than £890 per kWh. A quote well above the median should come itemised, so you can see whether backup, siting works or a new inverter account for the difference.
Sources (page last reviewed 3 November 2026)
- DESNZ: MCS certified domestic battery installation statistics (April 2024 to March 2026 workbook, published 28 May 2026), checked 3 November 2026.
- HMRC: VAT on energy-saving materials and heating equipment (Notice 708/6), sections 2.1, 2.3 and 2.19, checked 3 November 2026.
- MCS: notifying distribution network operators (G98 and G99), checked 3 November 2026.
- BSI / DESNZ: PAS 63100:2024, battery energy storage systems in dwellings (PDF), checked 3 November 2026.
- Ofgem: review of typical domestic consumption values, decision (May 2026; values from 1 July 2026), checked 3 November 2026.
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