EICR Codes Explained: What C1, C2, C3 and FI Actually Mean for Your Rental

Most landlords know they need an Electrical Installation Condition Report (EICR) every five years, or at the start of a new tenancy. Fewer landlords know what to do when the report comes back with the word "satisfactory" crossed out and a list of codes next to it instead.

An EICR isn't a pass/fail certificate the way an MOT feels like one. It's a structured inspection report, and the electrician doing the inspection will log every observation against a standard coding system. Understanding that system is the difference between knowing exactly what's required of you and guessing — and guessing on electrical safety is exactly the kind of thing that goes wrong at the worst possible time.

The four codes, in plain English

C1 — Danger present. This means there's a risk of injury right now. The electrician should have already taken immediate action to make the installation safe before leaving the property — isolating a circuit, for example. A C1 observation is rare precisely because dangerous-on-the-spot issues tend to get fixed on the spot. If you see a C1 on a report, treat it as the electrician already having had to intervene, and confirm in writing what they did.

C2 — Potentially dangerous. This is the one landlords see most often. It means something is wrong that could become dangerous — degraded insulation, no earthing where earthing should exist, a consumer unit that doesn't meet current standards for fire containment. It isn't an emergency in the sense of "evacuate the property," but it does need remedial work, and under the regulations that apply to most private tenancies, that work has to happen within 28 days of the report (or sooner, if the report specifies a shorter window).

C3 — Improvement recommended. This is advisory. It flags something that doesn't meet the very latest wiring regulations but isn't a safety risk in itself — often because the installation was done to the standard that applied when it was installed, and standards have since moved on. You're not legally required to act on a C3, though a cautious landlord often does anyway, particularly if several C3s are clustering around the same part of the installation.

FI — Further investigation required. The electrician couldn't fully assess something without additional access or testing — behind a fixed panel, for instance, or a circuit they couldn't isolate safely during the visit. An FI needs following up and, depending on what it turns into, could resolve as anything from "no issue found" to a C1.

What "satisfactory" actually depends on

A report comes back as unsatisfactory if it contains any C1 or C2 codes, or any FI that hasn't been resolved. C3s alone don't make a report unsatisfactory — they're recommendations, not failures.

This matters because the obligation that follows from an unsatisfactory report is specific: get the remedial work for the C1s and C2s done within the deadline, and get a satisfactory report, follow-up certificate, or written confirmation from a qualified electrician that the work has been completed and the installation is now safe. Current government guidance sets this out for landlords in England, and the detail can shift, so it's worth checking current guidance rather than relying on what applied five years ago — but the shape of the obligation has stayed consistent: unsatisfactory report, fixed deadline, and a paper trail proving the fix happened.

Where this actually trips landlords up

It's rarely the C1s that cause problems — those get dealt with immediately because the electrician won't leave without doing something. It's the C2s that drift. A landlord reads "potentially dangerous," sees the property is occupied and the tenant hasn't complained, and the 28-day window quietly passes while a contractor gets booked in for "whenever's convenient."

The second place it trips landlords up is evidence. Getting the remedial work done isn't the end of the obligation — you need documentation showing it happened, dated, from a qualified person. A landlord who did the work but can't produce proof of it is in almost the same position as a landlord who never did the work, if a dispute or inspection ever asks for the paperwork.

The third is relying on memory across a portfolio. One property's C2 deadline is not the same date as another property's C2 deadline, and if you're tracking five, ten, or fifty properties by memory or by a spreadsheet nobody updates consistently, something eventually slips. This is the specific, narrow problem CertMinder UK exists to solve: it logs the actual deadline from the actual report, not a generic "five years from last EICR," and reminds you with enough runway to book a contractor properly rather than in a scramble on day 27.

Booking the remedial work itself

One thing worth saying plainly: CertMinder UK doesn't take a cut, a fee, or a kickback from any electrician or contractor you book through its work-order flow. We don't have a commercial reason to steer you toward one tradesperson over another, because there isn't one — the work-order tool exists to keep the record straight (who was booked, what they fixed, what they certified), not to monetise who gets the job. You stay the one deciding who does the work; we just make sure the decision and the deadline don't get lost in the same inbox as everything else.

A quick way to read your next EICR

When the report lands, don't just look at the headline "satisfactory" or "unsatisfactory" line. Scan for C1 first — if there's one, confirm what immediate action was taken. Then C2 — note the deadline, and book the work now rather than after a reminder chases you. Then FI — find out what further investigation is actually needed and who's doing it. C3s can wait for a sensible moment, like the next full rewire or renovation, but don't let them get mixed up in your head with the codes that carry a legal deadline attached.

This article is informational and doesn't constitute legal advice. Electrical safety obligations and deadlines are set out in current government and industry guidance — always check the guidance that applies to your tenancy type before relying on specific timeframes.