Solar panel prices have come down significantly over the past five years. But there is a wide range of quotes out there, and it is hard to know what is fair. This guide breaks down what you should expect to pay in 2026 for a domestic solar system in the UK, what affects the price, and where you can save money.
Solar panel costs by system size
These are fully installed prices including panels, inverter, mounting hardware, electrical work, scaffolding, and MCS certification. All prices reflect the current 0% VAT rate for residential installations.
| System Size | Panels | Cost Range | Best For |
|---|---|---|---|
| 3kWp | 7-8 | £3,500 – £4,500 | 1-2 bed / low usage |
| 4kWp | 10 | £4,200 – £5,200 | 2-3 bed semi |
| 5kWp | 12-13 | £4,600 – £5,800 | 3-4 bed detached |
| 6kWp | 15 | £5,500 – £7,000 | 4-5 bed / high usage |
| 8-10kWp | 20-25 | £7,500 – £10,000 | Large home / EV owner |
The most popular system size we install across Milton Keynes is 4-5kWp. It suits the typical 3-4 bedroom house and strikes the best balance between cost and output.
What affects the price
Two homes on the same street can get different quotes. Here is what drives the variation:
Panel brand and type
Budget panels cost less upfront but may produce slightly less per square metre and come with shorter warranties. Premium brands like SunPower or Longi offer higher efficiency (21-22%) and 25-year product warranties. The difference per panel is roughly £30 to £60, which adds up across a full system.
Roof type and access
A straightforward pitched roof with easy access is the cheapest to install on. The price increases if your roof requires:
- Additional scaffolding (dormer windows, L-shaped roofs, three-storey properties)
- Specialist fixings for slate or flat roofs
- Reinforcement for older roof structures
Most homes in Milton Keynes have standard concrete tile roofs, which are the simplest and cheapest to work with.
Inverter choice
A string inverter is the standard option and is included in the prices above. Microinverters or power optimisers cost an extra £500 to £1,200 but offer better performance where there is partial shading on the roof. We recommend them where it makes a measurable difference — not as a default upsell.
Scaffolding
Scaffolding is included in most quotes. For a standard two-storey house, expect scaffolding costs of £300 to £500 within the total price. Complex builds or multi-level scaffolding can push this higher.
The 0% VAT saving
Since April 2022, residential solar panel installations in the UK have been zero-rated for VAT. This applies to panels, batteries, inverters, and the installation labour. The policy is confirmed until at least March 2027.
On a £5,000 system, that is a saving of £1,000 compared to the standard 20% rate. On a solar and battery package at £8,000, you save £1,600.
There is no guarantee this will be extended beyond 2027. If you are considering solar, this is a strong reason to act sooner rather than later.
Adding a battery
A battery storage system adds £2,500 to £3,500 for a 5kWh unit, or £4,000 to £6,000 for a larger 10kWh unit. The most common choice for a household with a 4-5kWp solar system is a 5-6kWh battery.
Combined solar and battery packages typically cost:
- 4kWp solar + 5kWh battery: £6,800 – £8,200
- 5kWp solar + 5kWh battery: £7,300 – £8,700
- 6kWp solar + 10kWh battery: £9,500 – £12,000
A battery increases your self-consumption from around 40% to 70-80%, which means significantly higher savings on your electricity bill. Whether the extra cost is worth it depends on your usage pattern. If you are out during the day and use most electricity in the evening, a battery makes a big difference.
What should be included in the price
A reputable installer should include all of the following in their quote:
- Solar panels and mounting hardware
- Inverter (string or micro)
- All electrical work and grid connection
- Scaffolding
- MCS certification and registration
- DNO notification (letting the grid operator know about your system)
- System monitoring setup
- Product and workmanship warranties
If a quote does not include scaffolding, MCS certification, or DNO notification, ask why. These are standard and should not be extras.
How to avoid overpaying
Get at least three quotes and compare like for like. Check that each quote specifies the panel brand, inverter model, total kWp, and what is included. Be wary of quotes that are significantly below market rate — they may use inferior equipment or cut corners on installation quality.
An MCS-certified installer is non-negotiable. Without MCS certification, you cannot claim the Smart Export Guarantee (SEG) payments, and your system will not be eligible for future government incentives. Check our grants and incentives guide for more on what is available.
What to do next
Use our free solar calculator to get a quick estimate based on your home. It factors in your roof, location, and usage to give you a realistic cost and savings figure.
Want a proper quote? Call us on 07516 762540 or get in touch online. We offer free, no-obligation surveys across Milton Keynes and Buckinghamshire. Fixed pricing, no hidden extras.