How to choose a solar installer in the UK
The kit on your roof matters less than the company that fits it. A good installer sizes the system correctly, wires it safely, registers it so you get paid for exports, and is still around if something goes wrong in year eight. A poor one can leave you with a leaking roof, a system that underperforms, and no recourse. Choosing well isn't about luck; it comes down to a short list of checks anyone can run. Here's how to pick one you can trust.
Start with MCS certification
The first filter is simple: the installer must be MCS-certified. MCS, the Microgeneration Certification Scheme, certifies both the installer and the equipment to a recognised standard. It matters for two concrete reasons beyond quality: you can only claim Smart Export Guarantee payments on an MCS-certified install, and grants such as the heat-pump Boiler Upgrade Scheme require it too. No MCS certificate, no export income. What MCS does and how to check a certificate is covered in what is MCS certification.
Check the consumer code
MCS-certified installers must also belong to a consumer code, which gives you protection if things go wrong. The two main ones are RECC (the Renewable Energy Consumer Code, backed by the Chartered Trading Standards Institute) and HIES. Membership usually brings a deposit protection scheme and an insurance-backed workmanship guarantee, so the warranty survives even if the installer goes out of business. Many quality firms also hold TrustMark, the government-endorsed quality mark.
| Accreditation | What it covers |
|---|---|
| MCS | Installer + product standard; required for SEG and grants |
| RECC / HIES | Consumer code: deposit protection, insurance-backed guarantee, dispute resolution |
| TrustMark | Government-endorsed quality and trading-standards mark |
Get three quotes, and compare the spec
Always get at least three quotes. Not just for price, but because the spread tells you a lot: a quote far below the others usually cuts a corner somewhere, and one far above may be padding. The trap is comparing on the headline figure alone. Two quotes for the same roof can differ by thousands because of panel quality, inverter type, whether a battery is included, and the workmanship guarantee. Read each one line by line, the way how to read a solar quote sets out, before you compare totals.
Read the reviews, then dig past them
Star ratings are a start, but read the recent written reviews, especially the negative ones, and look for how the company responded. Patterns matter more than any single review: repeated mentions of missed appointments, slow aftercare or pushy sales are worth taking seriously. Ask the installer for references or recent local installs you can ask about. A confident, established firm will have them.
The sales tactics to walk away from
The solar industry has a long tail of high-pressure selling. None of the following should survive a calm second look:
- "Today-only" discounts. A genuine price doesn't evaporate at midnight. Pressure to sign on the first visit is the clearest red flag there is.
- A free survey that turns into a four-hour sit-down. A quote should be a quote, not a war of attrition.
- Savings claims with no workings. Any reputable installer will show how a figure was reached. Inflated, unexplained savings are a version of the myths in solar panel myths.
- Reluctance to give an MCS number or written quote. Both should be offered without being asked.
The detail most people miss
Ask who actually does the work. Some sales companies subcontract the install to a separate team, which can be fine, but you want to know who is responsible for the workmanship guarantee and who you call if a panel fails. Tie the warranty, the MCS certificate and the company you're paying together in your mind: if those three are the same accountable entity, you're in a much stronger position than if they're three different names on three different bits of paper.
Frequently asked questions
Shortlist MCS-certified installers who belong to a consumer code (RECC or HIES), get three quotes, compare the full spec rather than just price, read recent reviews, and avoid anyone using high-pressure sales tactics.
Not legally, but you can only claim Smart Export Guarantee payments and most grants on an MCS-certified install, so in practice it's essential.
Yes, at least three. The spread reveals padding or corner-cutting, and comparing specs side by side stops you buying on headline price alone.
A workmanship guarantee underwritten by an insurer, so the cover survives even if the installer stops trading. It usually comes with consumer-code membership.
Through MCS certification and consumer codes (RECC, HIES) rather than a single regulator. Those schemes set the standards and handle disputes.
The bottom line
Pick an MCS-certified installer in a consumer code, get three quotes, compare the spec not the sticker, and refuse to be rushed. Do those four things and you remove almost all the risk from the biggest decision in the whole process. The kit is commodity; the company is everything.