Why You Must Question Your Solar Quote
The average 4kW solar panel system in the UK costs between £6,000 and £9,000. That's a significant investment. Unfortunately, the industry has its share of aggressive sales tactics and opportunistic pricing. A recent investigation found that some companies were charging nearly double the market rate for identical systems.
Asking "is my quote fair?" isn't about being cheap; it's about being a savvy consumer. It ensures you get a good return on your investment and aren't subsidising an installer's lavish marketing budget.
The Most Important Metric: Cost Per Watt (£/W)
When you look at your quote, the total price is just one part of the story. The single most important metric for comparing quotes is the cost per watt (or cost per kilowatt).
To calculate this, you divide the total price of the system (before any battery costs) by the size of the system in watts.
Formula:
Total Price / (System Size in kW × 1000) = Cost per Watt
Example:
- Total Price: £7,500
- System Size: 4 kW (which is 4,000 watts)
- Calculation: £7,500 / 4,000 = £1.87 per watt
This figure allows you to compare quotes of different sizes on an apples-to-apples basis.
What is a Fair Price for Solar Panels in the UK (2026)?
Based on current market data, here are the average costs you can expect for a standard, MCS-certified solar panel installation in the UK:
| System Size | Average Price Range | Average Cost per Watt |
|---|---|---|
| 3 kWp | £4,500 - £6,000 | £1.50 - £2.00 |
| 4 kWp | £6,000 - £8,000 | £1.50 - £2.00 |
| 5 kWp | £7,500 - £10,000 | £1.50 - £2.00 |
| 6 kWp | £9,000 - £12,000 | £1.50 - £2.00 |
If your quote comes in significantly higher than this range (e.g., over £2.20/W), it should raise a red flag.
Factors That Influence Your Solar Quote
Not all systems are created equal. Here are some legitimate reasons why a quote might be higher:
Panel Quality: Tier 1 panels from brands like SunPower, LG, or Q-Cells cost more than lower-tier panels. They offer better efficiency, degradation rates, and longer warranties.
Inverter Type: Premium inverters from brands like SolarEdge or Enphase (especially microinverters) are more expensive than standard string inverters.
Roof Complexity: A complex roof with multiple angles, dormers, or difficult access will increase labour costs.
Scaffolding: The cost of scaffolding can add £500 - £1,500 to the total price.
Warranty: Longer workmanship warranties (10 years is standard) can add a premium.
The Easiest Way to Know for Sure
Feeling overwhelmed? You're not alone. Analysing quotes can be time-consuming and confusing.
That's why we built SolarVerify. Our free, independent tool analyses your quote in seconds. It compares your price against thousands of data points from across the UK market to give you a simple, unbiased verdict on whether your quote is fair, overpriced, or a great deal.
Don't guess. Get clarity.