The UK solar market is growing fast. So is the number of companies trying to take advantage of homeowners who do not know what a fair deal looks like. Most solar installers are honest. But the ones who are not can cost you thousands of pounds, leave you with a system that underperforms, or lock you into finance agreements you did not fully understand.
This is not a scare piece. It is a checklist. If you are getting solar quotes, run every company through these checks before you sign anything.
The "tonight only" quote
The most common pressure tactic in UK solar sales. A representative visits your home, shows you a price, and tells you the quote is only valid tonight. Or this week. Or until the end of the month. The urgency is manufactured. Solar panel prices do not change overnight because you did not sign a contract.
A legitimate installer will send you a written quote by email and give you as long as you need to decide. If the price genuinely changes (because of a supplier price increase, for example), they will tell you in advance and explain why. A quote that expires in 24 hours exists to stop you comparing it with other installers.
Fake or exaggerated accreditations
Some companies display logos on their website for accreditation schemes they do not hold. Others use phrases like "MCS-standard" or "working to MCS standards" which have no official meaning. Either a company is MCS-certified or it is not.
Check every claim. Go to mcscertified.com and use the "Find an Installer" search. If the company is not listed, they are not MCS-certified. Check their Companies House record at find-and-update.company-information.service.gov.uk to see how long they have been trading and whether there are any red flags in their filing history.
Bundled system pricing
A quote that says "4kW solar system: £8,500 all-in" tells you almost nothing. Which panels? Which inverter? Is a battery included? What about scaffolding, the DNO application fee, and the MCS registration? Bundled pricing exists to make it harder for you to compare quotes from different installers.
A proper quote itemises every component: panel brand and wattage, inverter brand and model, battery brand and capacity (if included), scaffolding, labour, DNO fees, and any finance charges. If an installer will not break the price down, ask why.
Inflated savings projections
Be suspicious of any installer who shows you a savings projection that seems too good to be true. The figures should be based on your actual electricity usage (from a recent bill), your roof's orientation and pitch, and current energy prices. If the installer is using generic national averages or projecting future energy price increases that nobody can predict, the numbers are not reliable.
A responsible installer will explain the assumptions behind their savings estimate and tell you what could make the actual figure higher or lower. They will not guarantee a specific pound figure because too many variables are outside their control.
Unsolicited contact
Cold calls and doorstep visits are not illegal in themselves, but they are the primary channel for pressure-based solar sales in the UK. If someone contacts you without you asking for it, be more cautious, not less. Check them against every point on this list before engaging.
If you are on the Telephone Preference Service (TPS) register and a company cold calls you about solar, that is a criminal offence under UK law. Report them to the ICO.
The checklist
- Check MCS certification at mcscertified.com. No listing means no certification.
- Check Companies House. How long have they been trading? Are their accounts filed and up to date?
- Ask for an itemised quote. If they will not break the price down, walk away.
- Get the quote in writing by email. Not on a tablet screen at your kitchen table.
- Take your time. Any pressure to sign immediately is a red flag.
- Verify savings projections are based on your actual usage, not generic averages.
- Read the finance agreement separately from the install contract. Know the APR, total repayable amount, and cooling-off terms.
- Check Trustpilot, Google Reviews, and ask for references from recent customers in your area.
- Confirm who actually does the installation. Is it the company's own team or subcontractors?
- Ask about the workmanship warranty. Is it insured? Through which scheme?
What a legitimate process looks like
You contact the installer, not the other way around. The consultation is with a qualified engineer, not a commission sales rep. The quote arrives by email, itemised, with no expiry date. You are given time to compare it with other installers. The installer is MCS-certified and can prove it. The installation is done by the company's own employed team. The warranty is in writing and backed by an insured guarantee scheme.
That is the standard. Anything less should make you ask questions.
