EICR codes explained: C1, C2, C3 and FI
Most confusion about EICRs comes down to four codes. Once you know what they mean, an unsatisfactory report stops looking like a disaster and starts looking like a list of jobs.
C1: danger present
A C1 means there is a risk of injury right now. Exposed live parts behind a broken socket front, a damaged cable someone could touch, a conductor connected to the wrong terminal.
A competent electrician makes a C1 safe on the day wherever possible, with your permission, and tells you immediately rather than waiting for the report to land. A C1 always makes a report unsatisfactory.
C2: potentially dangerous
A C2 is not dangerous while everything works as intended, but it becomes dangerous if something else fails. Missing main protective bonding to the gas or water service is the classic example, as is an absent circuit protective conductor on a lighting circuit.
C2 is the code that generates most remedial work, and it also makes a report unsatisfactory. It is worth asking your electrician to show you each C2 in the property rather than relying on the photographs alone.
C3: improvement recommended
A C3 means the installation is safe but does not meet what would be required if it were installed today. The most common one by far is no RCD protection on socket circuits in older boards.
C3 observations do not fail a report. You do not have to act on them, though several C3s together often make a consumer unit upgrade the sensible option rather than a string of separate repairs.
FI: further investigation required
FI means something could not be assessed during the inspection and needs more work to establish whether it is a fault. Concealed junction boxes, circuits that could not be traced, and readings that do not make sense together are typical triggers.
An FI makes a report unsatisfactory, which surprises people. It is not the electrician being awkward: it means an unknown exists and no honest verdict can be given until it is resolved.
Which codes fail a report
Any C1, C2 or FI results in an unsatisfactory report. C3 alone does not. If a report is marked unsatisfactory and contains only C3 observations, ask for it to be explained, because that is not how the coding works.
- C1 - unsatisfactory, act immediately
- C2 - unsatisfactory, remedial work needed
- C3 - satisfactory, improvement worth considering
- FI - unsatisfactory until investigated
Official guidance
This guide is general information. For the final word on your own situation, use the official sources below.
Common questions
Can I dispute a code?
Yes. Coding involves judgement, and a reasonable electrician will explain the reasoning. A second opinion is entirely legitimate if you are not satisfied.
Do C3 items need fixing before a tenancy?
Not on their own. They are recommendations. Several related C3s can still point to a worthwhile upgrade.
Who fixes the C1 or C2 items?
Whoever you choose. There is no obligation to use the electrician who carried out the inspection, though it is often quicker and cheaper to do so.