The UK solar market is growing fast, and so is the number of companies trying to take advantage of homeowners who don't know what a fair deal looks like. Most installers do good work. The ones who don't can cost you thousands of pounds, leave you with an underperforming system, or lock you into finance you didn't fully understand.
Here's a checklist. If you're getting solar quotes, run every company through it before you sign anything.
The "tonight only" quote
The most common pressure tactic in UK solar sales. A rep visits your home, shows you a price, and says the quote is only valid tonight. Or this week. Or until the end of the month. The urgency is manufactured. Solar panel prices don't change overnight because you didn't sign.
A legitimate installer will email you a written quote and give you weeks, not hours, to decide. Ours expire in 30 days. If the price does change (after a supplier price increase, for example), they'll 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 for accreditation schemes they don't 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 isn't listed, they're not MCS-certified. Check their Companies House record at find-and-update.company-information.service.gov.uk to see how long they've been trading and whether there are any red flags in their filing history.
Vague quotes
A quote that says "4kW solar system: £8,500" and nothing else tells you very little. Which panels? Which inverter? Is a battery included? Does the price cover scaffolding, the DNO application and MCS registration? Ask the installer to confirm it in writing.
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 won't break the price down, ask why.
Inflated savings projections
Be wary of any savings projection that seems too good to be true. The figures should be based on your electricity usage (from a recent bill), your roof's orientation and pitch, and current energy prices. If the installer uses generic national averages or projects future price rises that nobody can predict, the numbers aren't reliable.
A responsible installer will explain the assumptions behind their savings estimate and what could make the figure higher or lower. They won't guarantee a specific pound figure, because too many variables are outside their control.
Unsolicited contact
Cold calls and doorstep visits aren't illegal in themselves, but they're the main channel for pressure-based solar sales in the UK. If someone contacts you without you asking, be more cautious, not less. Check them against every point on this list before engaging.
If you're on the Telephone Preference Service (TPS) register and a company cold calls you about solar, that is a breach of the Privacy and Electronic Communications Regulations (PECR). 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?
- Check what the total price covers, including scaffolding and the DNO application.
- 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.
- Check savings projections are based on your 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 does the installation: 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. Ours expire in 30 days, so you have time to compare with other installers. The installer is MCS-certified and can prove it. The company's own employed team does the installation. The warranty is in writing and backed by an insured guarantee scheme.
That's the standard. Anything less should make you ask questions.
