For a £7,000+ investment lasting 25 years, 15 minutes of due diligence is one of the best-value exercises you can do.
Check 1: MCS certification — mcscertified.com
The most important check. MCS certification is required for SEG eligibility and grant access.
- Go to mcscertified.com/find-an-installer
- Search company name or postcode
- Confirm: name matches, certification is 'current', and covers Solar PV
- Some companies trade under a different name to their Companies House name — search both if needed
Alliant on mcscertified.com
Check 2: NICEIC approval — niceic.com
Covers electrical installation standards. NICEIC-approved contractors can self-certify electrical work under Part P — no local authority inspection needed.
- Go to niceic.com/find-a-contractor
- Search by company name or postcode
- Confirm listed and current
NAPIT is an alternative approved body offering equivalent status — equally valid.
Check 3: TrustMark — trustmark.org.uk
The government-endorsed quality scheme. TrustMark-registered businesses have agreed to a code of conduct, consumer protection standards and a formal complaints process.
- Use the 'Find a Tradesman' search at trustmark.org.uk
- Confirm registration is current and covers Renewable Energy / Solar PV
Check 4: HIES or RECC membership
Consumer protection schemes that provide deposit protection and dispute resolution. At least one adds meaningful protection on top of the technical certifications.
- HIES: hiesscheme.org.uk — member search
- RECC: recc.org.uk — member search
If an installer is a member of neither, ask why. Code membership is a condition of some grant scheme participation.
Check 5: Companies House
Confirms the company is a registered legal entity, how long it has been trading, the directors, and any concerns.
- Go to find-and-update.company-information.service.gov.uk
- Search by company name or number
- Check status is 'Active', incorporation date, registered address, named directors
- Look for trading history of 2–3+ years for a 25-year investment
Alliant passes all five checks
MCS, NICEIC, TrustMark, HIES and Companies House — all public, all verifiable.
Summary: 15 minutes, five checks
| Check | Where to verify | Takes |
|---|---|---|
| MCS certification | mcscertified.com/find-an-installer | 2 minutes |
| NICEIC / NAPIT approval | niceic.com or napit.org.uk | 2 minutes |
| TrustMark registration | trustmark.org.uk | 2 minutes |
| HIES or RECC membership | hiesscheme.org.uk or recc.org.uk | 2 minutes |
| Companies House | companieshouse.gov.uk | 3–5 minutes |
What to do if a check fails
- MCS not current or not found: do not proceed. There's no acceptable substitute.
- NICEIC / NAPIT not found: ask directly. They may operate under a different name. If they can't verify, question the electrical certification.
- TrustMark not found: ask why. Doesn't automatically disqualify, but removes a layer of protection.
- Companies House shows recent incorporation or unusual structure: ask about trading history. Some legitimate companies restructure or trade through different entities.
A legitimate installer welcomes these checks. An installer who becomes defensive when you mention verifying credentials has told you something important.
Frequently asked questions
What if the installer is a sole trader rather than a limited company?
Sole traders aren't on Companies House in the same way, but they should still hold MCS, NICEIC and consumer code memberships — these are individual certifications. A sole trader with full credentials is a legitimate installer; the Ltd structure's protection is absent but the technical credentials are the same.
Can I check how long an installer has been MCS certified?
The MCS register shows current status but not full history. Companies House is the better source for trading history — it shows incorporation date and full filing history.
If the installer subcontracts the electrical work, does the subcontractor also need to be NICEIC?
Yes. The electrician carrying out the wiring and consumer-unit connection must be NICEIC (or NAPIT) approved to self-certify under Part P. Verify their credentials separately.
