Does a C3 mean the EICR has failed?

No. A C3 is a recommendation for improvement. It does not make the report Unsatisfactory, and a report whose only observations are C3 is Satisfactory.

Does an FI make an EICR Unsatisfactory?

Not on its own. Under BS 7671:2018+A4:2026, FI is an advisory code alongside C3 and does not affect the overall assessment. For a rented home in England, though, the government’s landlord guidance still tells the landlord to have the investigation carried out.

How long does a landlord have to fix a C1 or C2?

In England, work the report calls for must be completed within 28 days of the inspection, or sooner if the report specifies a shorter period. Written confirmation that it has been done then goes to each tenant and the local housing authority within 28 days of the work being completed. A C1 is dangerous now, so in practice it is dealt with straight away.

Will the electrician fix a C1 before leaving?

The inspector may make a C1 hazard safe before leaving, for example by isolating the circuit, which is what the government’s landlord guidance describes. Making it safe is not the same as repairing it: the repair is separate work, certified on its own document.

Are NICEIC condition report codes different?

No. The codes C1, C2, C3 and FI come from the model report format published with BS 7671, so they mean the same on a report from an NICEIC-registered contractor, an NAPIT-registered one, or any other.

Who decides which code an observation gets?

The inspector who carried out the inspection, using their professional judgement about how serious the defect is. If you disagree with a code, ask them to explain it; a second opinion from another qualified electrician is also an option.

Can a report have no observations at all?

Yes. If nothing needs recording, the report says no remedial action is required and is Satisfactory. On an older installation it is unusual, so it is reasonable to ask the inspector what was inspected and tested.

UK electrical certificates explained

EICR observation codes explained: C1, C2, C3 and FI

On an EICR, C1 means danger is present, C2 means potentially dangerous, C3 means improvement recommended and FI means further investigation is advised. Any C1 or C2 makes the report Unsatisfactory; C3 and FI on their own do not. This guide explains each code, how it affects the outcome, and what the person responsible has to do about it.

Last updated 27 October 2026. Written by the CertSync team and checked against the standards.

The short answer

Every observation on an Electrical Installation Condition Report is given one code. C1 is a danger now and needs immediate action. C2 is a condition that could become dangerous and needs urgent action. C3 is a recommendation to improve something that falls short of the current edition of BS 7671 but is not dangerous. FI means the inspector found something they could not reach a conclusion on during the inspection and recommends looking into it. The report is Unsatisfactory if it records any C1 or C2, and Satisfactory otherwise. For a rented home in England, where the report shows the installation is or may be unsafe, the remedial or investigative work it calls for must be done within 28 days of the inspection, or sooner if the report says so.

C1 — danger present

A C1 means someone could be hurt now: the defect is dangerous as it stands, and putting it right cannot wait. Exposed live parts that can be touched are the obvious case.

The government’s guidance for landlords notes that the inspector may make a C1 hazard safe before leaving the property, for example by isolating the circuit. Where the danger stays in place, the person responsible for the installation should be told straight away and in writing. A Danger Notice is the written record of that warning, separate from the report.

C2 — potentially dangerous

A C2 is not dangerous at this moment, but would become dangerous if something foreseeable happened, such as a fault on the circuit or a protective device failing to operate. It needs urgent remedial action.

The line between C1 and C2 is the inspector’s professional judgement about how immediate the risk is. Both have the same effect on the report: either one makes it Unsatisfactory.

C3 — improvement recommended

A C3 records something that does not meet the current edition of BS 7671 but is not dangerous. It is common on older installations that were built correctly to an earlier edition, where the rules have since moved on.

A C3 does not make the report Unsatisfactory, and the government’s landlord guidance says no further work is needed for a report with only C3 items to count as Satisfactory. It is still worth reading: it is the inspector telling you what they would improve, and why.

FI under BS 7671:2018+A4:2026

FI is used when the inspector has seen something that might be a problem but could not reach a conclusion on it within the inspection that was agreed, for example because the cause sits behind a part of the building that was not opened up. On the A4:2026 model report the code reads “FI: further investigation is advised”.

Under A4:2026, FI sits with C3 as an advisory code. It does not affect the overall assessment on its own, so a report can be Satisfactory and still carry an FI. The model form adds that advisory items should still be given due consideration.

For a rented home in England, treat an FI as something to act on. The government’s landlord guidance tells landlords to make sure investigative work for an FI is carried out. Where the report also shows the installation is or may be unsafe, the rented-sector regulations give 28 days, or any shorter period the report sets, for that investigation.

Satisfactory or Unsatisfactory

An EICR ends with one overall assessment of whether the installation is suitable for continued use. It is Unsatisfactory if any observation is coded C1 or C2. If the only observations are C3 and FI, or there are none at all, it is Satisfactory.

The codes are set observation by observation, so the summary cannot be read on its own. A Satisfactory report with an FI still has an open question on it, and an Unsatisfactory report tells you exactly which items have to be dealt with to put it right.

What has to happen next, and by when

For a privately or socially rented home in England, the Electrical Safety Standards in the Private Rented Sector and Social Rented Sector (England) Regulations 2020 set the timescale. Where the report says further investigative or remedial work is necessary, a qualified person must carry it out within 28 days of the inspection, or within any shorter period the report specifies.

Once it is done, the landlord must get written confirmation from a qualified person that the work has been carried out, and supply it, with a copy of the report, to each existing tenant and to the local housing authority within 28 days of the work being completed. The authority can also ask for a copy of the report itself, and must receive it within 7 days of asking in writing.

The remedial work is certified on its own document: a Minor Works certificate for a change to an existing circuit, or an Electrical Installation Certificate for a new circuit or a consumer unit replacement. For a home that is not rented out, these rented-sector deadlines do not apply, but the codes still tell you the urgency: C1 at once, C2 as soon as it can be arranged.

The same codes whichever scheme the electrician belongs to

The four codes are part of the model report format published alongside BS 7671, not a system belonging to any one registration scheme. An EICR from an electrician registered with NICEIC, NAPIT or any other scheme uses C1, C2, C3 and FI with the same meanings, and a report is coded the same way whether or not the electrician belongs to a scheme at all.

Recording codes in CertSync

In CertSync each observation carries its code, a plain description and any photos you attach. The report cannot be marked Satisfactory while a C1 or C2 is recorded, and where there is a C1 or C2 it records the name of the person you told and when. You still choose the overall outcome yourself.

Frequently asked questions

Does a C3 mean the EICR has failed?: No. A C3 is a recommendation for improvement. It does not make the report Unsatisfactory, and a report whose only observations are C3 is Satisfactory.
Does an FI make an EICR Unsatisfactory?: Not on its own. Under BS 7671:2018+A4:2026, FI is an advisory code alongside C3 and does not affect the overall assessment. For a rented home in England, though, the government’s landlord guidance still tells the landlord to have the investigation carried out.
How long does a landlord have to fix a C1 or C2?: In England, work the report calls for must be completed within 28 days of the inspection, or sooner if the report specifies a shorter period. Written confirmation that it has been done then goes to each tenant and the local housing authority within 28 days of the work being completed. A C1 is dangerous now, so in practice it is dealt with straight away.
Will the electrician fix a C1 before leaving?: The inspector may make a C1 hazard safe before leaving, for example by isolating the circuit, which is what the government’s landlord guidance describes. Making it safe is not the same as repairing it: the repair is separate work, certified on its own document.
Are NICEIC condition report codes different?: No. The codes C1, C2, C3 and FI come from the model report format published with BS 7671, so they mean the same on a report from an NICEIC-registered contractor, an NAPIT-registered one, or any other.
Who decides which code an observation gets?: The inspector who carried out the inspection, using their professional judgement about how serious the defect is. If you disagree with a code, ask them to explain it; a second opinion from another qualified electrician is also an option.
Can a report have no observations at all?: Yes. If nothing needs recording, the report says no remedial action is required and is Satisfactory. On an older installation it is unusual, so it is reasonable to ask the inspector what was inspected and tested.

Disclaimer

This guide is general information, not professional advice, and is not a substitute for the current gov.uk guidance, the current edition of BS 7671 or independent legal advice. Landlord duties can change and you are responsible for checking the current position. The contractor named on a certificate is responsible for what it certifies.

Sources & official guidance

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