You can legally have solar panels fitted by any competent electrician. But if the installation is not MCS certified, you cannot register for the Smart Export Guarantee, which means you generate electricity for the grid and are paid nothing for it.
Over twenty five years that is worth thousands of pounds. It is the single most consequential thing to get right, and it is decided before you sign.
Why MCS matters when there is no grant
With a heat pump, MCS certification is the gate to £7,500. The reason is obvious and no installer forgets to mention it.
Solar has no grant, so the connection is less visible and gets skated over. Here it is plainly: GOV.UK’s Smart Export Guarantee guidance requires that your installation and installer are certified through the Microgeneration Certification Scheme, or through a scheme accredited as equivalent. Suppliers apply that condition. An uncertified installation is an installation that cannot be paid for its exports.
On our export rates page we set out why the difference between a poor and a good export tariff is worth around £4,500 over the life of a system. Without certification you are not choosing between tariffs. You have none.
The alternative nobody mentions. MCS is not the only recognised route. Flexi-Orb is also recognised for Smart Export Guarantee purposes and works on similar quality assurance principles. It is far less common, but an installer offering Flexi-Orb rather than MCS is not automatically disqualifying. Ask which scheme they are certified under and verify it.
What changed in 2026, and why most guides have it wrong
MCS is migrating every certified installer onto a redeveloped scheme, a process due to complete by 31 March 2027. The significant change is that MCS now handles consumer protection directly, through its own customer commitment and a central complaints route.
Which means membership of a consumer code such as RECC or HIES is no longer a mandatory condition of MCS certification. A great many guides published this year still state that it is.
The practical consequence for you is that during the migration, two equally legitimate MCS installers may have different arrangements:
- An installer on the redeveloped scheme provides MCS-approved financial protection for each installation
- An installer still on the previous scheme holds RECC or HIES membership, which brings deposit protection, workmanship warranties and independent dispute resolution
Either is fine. What is not fine is neither. Ask which one applies to your installation and get the answer in writing. Whichever route, you should receive an insurance-backed guarantee.
This is the same position we set out for choosing an MCS heat pump installer, because it is one scheme covering both technologies.
Verify it yourself, in two minutes
Logos on a website mean nothing. They can be copied, and they are.
- Search the installer at mcscertified.com. Check the certification is live, in the company’s own name, and covers solar PV specifically. A company certified for heat pumps is not thereby certified for solar.
- Check the trading name matches the legal entity on the quote. Sales operations sometimes trade under a name that differs from the certified company.
- Look the company up at Companies House. Free, and it tells you how long it has traded, whether accounts are filed on time, and whether there is any insolvency history. We suggested this on our batteries page for manufacturers, and it applies at least as much to the company doing the work.
- If they claim a consumer code, verify it at recc.org.uk or the HIES site rather than taking the badge at face value.
The question that separates a survey from a sales visit
MCS-certified installers estimate generation using a standard method, MIS 3002. The calculation is system size in kWp, multiplied by a location value called Kk, multiplied by a shade factor.
MCS requires installers to provide the assumptions behind their estimate. So:
Ask for the Kk value and the shade factor.
Those two numbers tell you whether a proper assessment happened. A shade factor of 1.00 means they have found no shading at all, which on a British roof with a chimney deserves a question. A quote that cannot produce either number is not an MCS-standard calculation, whatever the paperwork says.
It also lets you sanity check the estimate against an independent tool such as the European Commission’s PVGIS, which is free. An estimate materially above an independent calculation is worth challenging before you sign, not after.
What should be in the quote
Should be included: panels and their wattage, the inverter, mounting system, all electrical work and isolation, scaffolding, the DNO notification, MCS certification and the handover pack you need for your export application.
Commonly missing, and worth asking about explicitly:
- Bird protection mesh. Inexpensive while the scaffolding is up, expensive once it has gone.
- A consumer unit upgrade, if your board cannot take the installation.
- Optimisers or microinverters. Justified where there is shading, sometimes quoted as standard where there is not.
- Scaffolding on awkward access. Usually included, occasionally not.
- A battery. Treat it as a separate decision with its own arithmetic rather than a line on the solar quote.
And compare quotes on total installed price against system size in kW. Panel counts are not comparable because wattages differ. Our solar cost page gives the official figures to benchmark against.
What happens if the installer goes bust
Not a remote possibility in this sector, and the reason deposit protection exists.
Before the work is done, your deposit is protected only if the installer’s consumer code or MCS financial protection covers it. Ask what happens to your money if the company fails between deposit and installation, and get the answer in writing.
Pay some of it by credit card. Section 75 of the Consumer Credit Act 1974 makes your card provider jointly liable with the seller where the goods or services cost over £100 and not more than £30,000, which covers essentially every domestic solar installation. The useful part, and the part most people do not know: you do not have to put the whole amount on the card. Paying the deposit by credit card can cover the full value of the purchase. It applies to credit cards only, not debit or charge cards.
After the work is done, your workmanship guarantee is only as good as the company behind it, unless it is insurance backed. An insurance-backed guarantee is underwritten by a third party and survives the installer’s failure. A ten year guarantee from a company with three years of trading history and no insurance backing is worth considerably less than it sounds.
The certificate matters here too. Your MCS certificate should arrive within roughly ten working days of commissioning. If the installer fails before issuing it, you may struggle to register for export payments. Chase it, and do not treat the job as finished until you have it.
Sales tactics worth recognising
Solar has a longer history of aggressive selling than most home improvements, and some of it persists.
- A discount that expires today. No legitimate installation price depends on signing this evening.
- A generation estimate with no assumptions attached. Covered above. Ask for the Kk and shade factor.
- Payback figures with no self-consumption question. If nobody has asked whether you are home during the day, the payback figure is decoration. Our worth it page explains why that question decides the answer.
- Finance presented as the headline. A monthly figure is not a price. Ask for the total amount payable and the APR.
- A battery bundled without discussion. Ask what the payback is without it.
- Free solar in exchange for your roof. Rent-a-roof arrangements give the export income to someone else and can complicate selling the house. Read the lease term before anything else.
A sensible process
- Get three quotes, from companies you found rather than companies that found you.
- Verify certification at mcscertified.com before the survey, not after.
- Insist on a roof survey. A quote produced from satellite imagery alone has not assessed your shading.
- Ask every installer for the Kk value, the shade factor and the estimated annual kWh.
- Compare on total price against kW, and on what is included rather than headline figures.
- Check protection arrangements and get them in writing.
- Do not pay a large deposit, and pay by credit card where possible.
A good installer will spend time on your roof and be comfortable showing their working. One who will not explain how they reached their generation figure has told you something useful.
Frequently asked questions
These come up most often when people start getting solar quotes.
Do solar panels have to be installed by an MCS-certified installer?
Not legally, but without MCS certification or an equivalent recognised scheme you cannot register for the Smart Export Guarantee, so you would not be paid for anything you export. In practice that makes certification close to essential.
Is RECC or HIES membership still required?
Not under the redeveloped MCS scheme, which now handles consumer protection directly. Many guides still say it is mandatory. During the migration, which runs to 31 March 2027, installers may be on either arrangement. Ask which applies to your installation.
How do I check an installer is MCS certified?
Search for them at mcscertified.com. Check the certification is live, in the exact legal name on your quote, and covers solar PV rather than another technology. Do not rely on a logo on a website.
What is a Kk value and why should I ask for it?
It is the annual kWh per kWp for your location, orientation and roof pitch, used in the MCS generation calculation along with a shade factor. MCS requires installers to provide their assumptions, so asking for both lets you check the estimate yourself.
What happens if my solar installer goes out of business?
It depends on what protection was in place. Deposit protection covers money paid before the work; an insurance-backed guarantee covers workmanship afterwards. Paying by credit card gives you rights under Section 75 of the Consumer Credit Act for purchases over £100 and up to £30,000, and covers the full value even if you only paid the deposit by card.
When should I receive my MCS certificate?
Usually within around ten working days of commissioning. You need it to register for export payments, so chase it if it does not arrive and do not consider the job complete without it.
Last updated 18 September 2026. Smart Export Guarantee certification requirements as set out in GOV.UK guidance. MCS scheme structure, the redeveloped installer scheme and its 31 March 2027 completion date, and the change to consumer code requirements are drawn from MCS and industry sources; note that many published guides still describe consumer code membership as mandatory. Generation methodology from MCS standard MIS 3002. Section 75 of the Consumer Credit Act 1974 applies where the goods or services cost over £100 and not more than £30,000, and covers the full purchase value even where only part was paid by credit card. Verify any installer’s certification directly at mcscertified.com. Written by Ben Jardine.