The short answer
For a typical UK home, a fully installed solar panel system costs in the region of £5,000 to £11,000, depending mainly on the size of the system. A small 3kWp array suited to a one or two-bedroom home is often around £5,000–£7,000, while a 4kWp system — the most common domestic size — typically lands around £6,000–£9,000, and larger 5–6kWp systems run higher. Adding a battery increases the total by roughly £2,000–£5,000. Since the 0% VAT rate introduced for domestic solar in Great Britain, the prices you are quoted should already exclude VAT, lowering the bill. The figure varies with roof type, scaffolding needs and panel quality, so always compare like-for-like specifications.
Solar panel prices fall into fairly predictable ranges once you know the system size. The bigger variables are battery storage, your roof, and the quality of equipment quoted.
Typical UK installed cost
- 3kWp system~£5,000–£7,000
- 4kWp system (common)~£6,000–£9,000
- 5–6kWp system~£9,000–£11,000+
- Add a battery+£2,000–£5,000
- VAT (domestic, GB)0% until March 2027
Typical cost by system size
The single biggest driver of price is the size of the system, measured in kilowatts-peak (kWp). Larger arrays cost more in total but tend to be a little cheaper per kWp because fixed costs like scaffolding and labour are spread across more panels. The table below shows indicative installed ranges for a standard pitched-roof home in Great Britain, with 0% VAT applied.
| System size | Rough number of panels | Typical installed cost | Suited to |
|---|---|---|---|
| 3kWp | ~7–8 panels | ~£5,000–£7,000 | 1–2 bed home, lower usage |
| 4kWp | ~10 panels | ~£6,000–£9,000 | Typical 3-bed family home |
| 5kWp | ~12–13 panels | ~£8,000–£10,000 | Larger home / higher usage |
| 6kWp | ~14–16 panels | ~£9,000–£11,000+ | Large home, EV or heat pump |
Indicative installed costs for guidance, 0% VAT applied. Sources: Energy Saving Trust; MCS. Actual quotes vary with roof type, equipment and location.
What makes up the cost
A solar quote bundles several elements into one figure. Understanding the breakdown helps you compare quotes fairly:
- Panels: the modules themselves. Higher-efficiency or premium-brand panels cost more but generate more from the same roof area.
- Inverter: converts the panels' DC electricity to AC for your home. A string inverter is standard; microinverters or optimisers cost more but can help on shaded or complex roofs.
- Mounting and scaffolding: rails, fixings and the access scaffold. Complex or tall roofs raise this.
- Labour and design: the survey, electrical work, installation and commissioning by an accredited installer.
- Battery (optional): a home battery adds roughly £2,000–£5,000 depending on capacity.
Two quotes for the same kWp can differ because of equipment quality, roof complexity and whether storage is included. Always check the specification, not just the headline price.
How 0% VAT and your roof affect the figure
Two factors commonly move a quote up or down from the typical range:
- 0% VAT: the UK government applies a 0% VAT rate to qualifying domestic solar installations in Great Britain, in place until 31 March 2027, after which it is currently set to revert to 5%. A compliant quote should already have this applied, which lowers the total compared with the old 20% rate.
- Roof type and access: a standard south-facing pitched roof with slate or tile is the lowest-cost to fit. Flat roofs need ballasted or angled frames; older or fragile roofs may need extra work; and a high or awkward roof increases scaffolding cost. These can add several hundred pounds or more.
- Number of roof faces: splitting an array across two or three roof planes can add components and labour compared with a single clean run of panels.
Because of these variables, the only reliable way to know your cost is a survey of your specific roof. The ranges above are a sound starting point for budgeting.
Frequently asked questions
Is VAT charged on solar panels in the UK?
Domestic solar installations in Great Britain currently qualify for 0% VAT, in place until 31 March 2027, after which the rate is set to return to 5%. A compliant installer quote should already reflect the 0% rate, so the price you see should not have VAT added on top.
Why do solar quotes vary so much?
Quotes differ because of system size, panel and inverter quality, roof complexity, scaffolding needs and whether a battery is included. A larger or premium system costs more, and a difficult roof adds labour and access costs. To compare fairly, line up the kWp, equipment brands and storage across each quote.
Is it cheaper to buy a bigger system?
Per kilowatt, larger systems are usually slightly cheaper because fixed costs like scaffolding and labour are spread across more panels. However, the system should be sized to your electricity use and roof space — a bigger array only pays back well if you use or export enough of the extra generation.
Sources & further reading
- Energy Saving Trust — solar panels
- MCS — find a certified solar installer
- GOV.UK — VAT on energy-saving materials
Figures on this page are typical UK ranges drawn from published sources and depend on your specific home. They are guidance, not a quotation or guaranteed saving.