How to check a solar installer before you sign

How can I check if my installer is MCS certified?

Use MCS's own search, Find an Installer, for MCS certified installers (sometimes called MCS accredited installers). You can search by the installer's name or certification number, and filter by technology to check the business is MCS certified for what you are having installed: solar PV, and battery storage if the quote includes one [1]. A result shows the certification number, address, telephone, regions covered, whether it is registered for the Boiler Upgrade Scheme and its certification body [1]. MCS warns that some installers pose as MCS certified when they are not; if in doubt, its helpdesk on 0333 103 8130 can check [2][4].

Then compare with the quote. MCS's guidance says a quotation should carry the business's MCS certification number and, where it applies, its company registration number [12], so check they match the firm you found. Sole traders and ordinary partnerships have no company number.

Which MCS scheme is the installer on?

Two MCS schemes run side by side until 31 March 2027: the current scheme and the redeveloped scheme [5]. The protection you get depends on which one the installer is certified under, and the search result does not show it [1], so ask and get the answer in writing.

Ask to see the protection documents as well as the scheme name. Before you pay a deposit, ask in writing how it is protected and what happens to it if the installer stops trading before the job is finished. For the workmanship guarantee and any insurance or financial protection product, check who provides the cover, what installation problems it covers, and any exclusions, claim limits or excess. What you should get depends on the installer's MCS scheme (see the table), and some documents, such as an insurance-backed guarantee, arrive only after the work is finished. Keep them all with the contract [6][8][9].

How do you check RECC or HIES membership?

RECC's Find a Code Member searches by name, region or technology; RECC says only businesses on that list are members and it is updated each week [13]. HIES members can be found through the HIES search linked from the Chartered Trading Standards Institute's Approved Code page [14]. A current-scheme installer should be in a code like these [6]. Under the redeveloped scheme, a firm outside any code is not breaking MCS rules [10]: check the financial protection product instead, which the quote should name [7][12].

What does Companies House show?

The company record, free to view [15]:

You can also set up free alerts for changes [15]. Check the company number on the quote leads to the same business, and ask about anything that does not fit, such as a different name or a very recent change of directors.

Who signs off the building work?

In England, members of a government-authorised competent person scheme can self-certify certain types of building work instead of getting building regulations approval [16]. GOV.UK lists the schemes by type of work:

Where a scheme member does the work, the building regulations compliance certificate should reach the occupier within 30 days of completion [18]. These lists are for England; we have not covered the other nations here.

Do you have to be MCS registered to install solar?

No: MCS says its certificate is not a mandatory or legal requirement for installing a system [4]. But MCS certification is a requirement for many government incentives [3]. To be paid under the Smart Export Guarantee in Great Britain, solar PV up to 50 kW needs both the installation and the installer certified under MCS or an equivalent scheme [17][19]. Certification means the installer works to MCS installation standards with MCS certified products [3]; it is not a promise the job will go well, which is why the guarantees, financial protection and complaints route above matter.

When should you walk away from an installer?

The first three come from MCS's own warnings to consumers [2]:

• A caller who says MCS passed on your details. MCS says it never shares your details with installers or asks them to contact you, and never cold calls [2].
• An urgent deal at the door or on the phone. MCS's advice is not to sign up for anything on the spot [2].
• An offer of a free check, an upgrade or an extended warranty, or a claim that parts need replacing, which MCS lists among the approaches to be wary of [2].
• Ask before you sign if the business does not appear on the MCS search under the name or certification number on its quote, or the quote names a different business. A trading name can explain it, but get the answer in writing [1][12].

To report a suspected fraud, MCS points to the Citizens Advice consumer service on 0808 223 1133 [2]. If the firm checks out but you are unsure about the price, compare it with another: get a second quote, and see how to check a solar quote.

The routine, in order

1. Search MCS. Find the firm on MCS's Find an Installer by name or certification number, filtered for solar PV, and battery storage if one is quoted.
2. Ask which MCS scheme. Current or redeveloped, in writing.
3. Check the protection. Current scheme: the RECC or HIES membership and the insurance that backs the workmanship guarantee. Redeveloped scheme: the named MCS approved financial protection product.
4. Check Companies House. If the firm is a registered company: its date of incorporation, officers and any insolvency record. Sole traders and ordinary partnerships are not on it.
5. Match the paperwork. The business name, MCS certification number and, for a registered company, the company number on the quote should match what you found; ask about any difference.
6. Building work sign-off. In England, ask which competent person scheme will self-certify the work, or who will get building regulations approval.

We do not rank installers. Whoever you use, including an installer you reach through Worthwatt, these checks are worth running yourself. How the installation itself goes is in solar panel installation.