A Minor Electrical Installation Works Certificate, usually shortened to minor works certificate, is issued by the electrician who did the work. It applies to additions and alterations to an existing installation that do not extend to the provision of a new circuit, and it covers the specific work carried out plus testing of the circuit affected.
Adding a socket to an existing ring, moving a light switch, or fitting a fused spur for an appliance are the ordinary cases.
The paperwork family, and who issues what
Confusion here is common and expensive, because the documents look similar and do entirely different jobs.
An Electrical Installation Certificate is the one for new work of any size: a new installation, a rewire, a new circuit, or a consumer unit replacement. It certifies the design, construction, inspection and testing of that work against BS 7671. The electrician issues it.
A minor works certificate is the smaller sibling for additions and alterations that stop short of a new circuit. Again, the electrician issues it.
An Electrical Installation Condition Report is not a certificate for new work at all. It is a periodic assessment of an existing installation, recording coded observations about its condition. Different purpose, different scope, and it requires an inspector registered for that scope.
A Building Regulations Compliance Certificate is the one people most often assume their electrician hands over, and it does not come from the electrician. Where notifiable work has been self-certified, the scheme operator issues it after the electrician notifies the completed work, and the scheme simultaneously tells the local authority. It confirms compliance with Part P rather than with the wiring regulations.
So a consumer unit change should generate an installation certificate from the electrician and a compliance certificate from the scheme. A socket added to an existing circuit generates a minor works certificate and nothing else, because there is nothing to notify.
Why you get one even when nothing is notifiable
Notifiable work in England is limited to installing a new circuit, replacing a consumer unit, and altering circuits within a special location. Most small jobs fall outside all three.
That does not remove the obligation to do the work properly. Approved Document P states that all electrical installation work in a dwelling is subject to requirement P1, and that non-notifiable work should be designed, installed, inspected, tested and certificated in accordance with BS 7671. Local authorities can take enforcement action where non-notifiable work is found to be unsafe.
The minor works certificate is how that testing gets recorded. It is the evidence that someone measured the circuit after altering it rather than connecting something and leaving.
What is on it
The certificate identifies the work carried out, the circuit affected, and the results of the testing done on that circuit: continuity, insulation resistance, earth fault loop impedance, polarity, and the operation of any residual current device protecting it. It carries a declaration that the work complies with BS 7671, and the signature and qualifications of the person who did it.
It also normally records the version of BS 7671 the work was certified against. The current version is BS 7671:2018+A4:2026, published on 15 April 2026, with the preceding version withdrawn on 15 October 2026. Certificates issued during that overlap may legitimately cite either.
What it does not do
It does not say anything about the rest of the installation. Testing is confined to the circuit that was worked on, so a minor works certificate for a new socket in the lounge tells you nothing about the state of the kitchen wiring, the earthing arrangements or the consumer unit. A condition report is the document that covers the installation as a whole.
It is also not proof of Building Regulations compliance for notifiable work, and cannot be substituted for one. If someone offers a minor works certificate for a consumer unit change, either the wrong certificate has been chosen or the work was not treated as notifiable, and both are worth resolving before final payment.
Keep them
File every electrical certificate with the deeds or wherever the house paperwork lives. They are cheap to keep and impossible to recreate.
The reason has sharpened recently. An enforcement notice for work that contravened the building regulations can now be served up to ten years after completion, extended from twelve months in April 2023, and it is served on the owner of the property rather than on whoever carried out the work. Ten years overlaps a typical period of ownership, which is why a buyer's solicitor now asks about electrical work that would once have been ancient history.
Where paperwork is missing for past work, a retrospective condition report is the cheapest step and often satisfies a buyer, without being a Building Regulations certificate. Regularisation through the local authority is the formal route for unauthorised work carried out on or after 11 November 1985, and the resulting certificate is evidence, though not conclusive evidence, of compliance.
What to ask for at quote stage
Ask which certificate the job will produce, who issues it, and when you will receive it. Getting that answer before work starts is considerably easier than chasing it afterwards.
Paperwork is the part of a job you keep long after the work is invisible.