This guide covers the best angle for solar panels in the UK: the optimum fixed tilt for different regions, how much output you lose on flatter or steeper roofs, and whether adjusting the angle through the year is worthwhile.
Quick answer: For a fixed south-facing system, the best angle in most of the UK is around 35 to 40° from horizontal. Most pitched roofs fall between 30 and 45°, which loses only a few per cent. Flat-mounted panels lose roughly 10 to 15%, and vertical panels about 30% or more over a year.
Why does tilt matter?
Panels produce the most when sunlight hits them square on. In the UK the sun is high in summer and low in winter, so a fixed panel is a compromise between the two. The best year-round angle is somewhat less than the latitude, because summer days contribute far more energy.
Best tilt by region
Approximate optimum fixed tilts for south-facing panels, from typical PVGIS results. Use PVGIS for your exact location.
| Area | Latitude | Optimum fixed tilt |
|---|---|---|
| Cornwall and the south coast | 50° | about 37° |
| London and the Midlands | 51 to 52.5° | about 37 to 39° |
| Northern England | 53.5 to 55° | about 38 to 40° |
| Central Scotland | 56° | about 39 to 41° |
| Northern Scotland | 57 to 59° | about 40 to 42° |
How much do you lose at other angles?
Approximate yearly output relative to the optimum for a south-facing system in southern England:
| Tilt | Output vs optimum |
|---|---|
| 0° (flat) | about 85 to 90% |
| 15° | about 94% |
| 30° | about 99% |
| 40° | about 100% |
| 60° | about 92% |
| 90° (vertical wall) | about 65 to 70% |
Flat roofs
On flat roofs, panels are usually tilted on frames at about 10 to 30°. Lower tilts let you fit more rows without shading, so the total output per roof can be higher even if each panel produces a little less. East-west low-tilt layouts are common on flat roofs.
Should you adjust the angle through the year?
For roof systems it is rarely practical. For ground mounts, vans or off-grid systems, changing the tilt two to four times a year can add a few per cent, and a steeper winter angle helps when winter output matters most. Our seasonal solar tilt calculator gives the angles.
Frequently Asked Questions
What angle should solar panels be in the UK?
About 35 to 40° for a fixed south-facing system.
Is a 45° roof good for solar?
Yes, it loses only a small amount compared with the optimum.
Do flat solar panels work in the UK?
Yes, but they produce around 10 to 15% less and collect more dirt; a slight tilt helps.
Are vertical solar panels worth it?
They produce less overall but relatively more in winter; balcony and wall systems use them.
Checked November 2026 by the Solaxyra Editorial Team. Sources: PVGIS (European Commission), Energy Saving Trust: Solar panels.