EICR Codes Explained: C1, C2, C3 and FI

Four short labels can determine the next conversation after an Electrical Installation Condition Report. C1 and C2 identify safety problems and make the report unsatisfactory. C3 recommends an improvement. FI flags a potential issue that the inspection could not fully classify. The codes are not prices, repair instructions or a verdict on the whole property. They are a way of recording the significance and urgency of individual observations.

If an EICR for a Cirencester or Cotswolds property contains one of these codes, start with the overall assessment and the exact observation. Then read the stated extent, limitations and test schedules. If you only receive a photograph of the observations page, ask for the complete report before making a decision or requesting a quotation.

C1, C2, C3 and FI at a glance

This summary follows Electrical Safety First's Best Practice Guide 4 and the IET model forms. The inspector still applies professional judgement to the evidence at the property. A list of generic examples cannot safely replace that judgement, because the same visible detail can have a different significance depending on the circuit, protective measures, environment and test results.

What makes an EICR unsatisfactory?

The IET's model EICR forms link an unsatisfactory assessment to dangerous C1 conditions and potentially dangerous C2 conditions. One C1 or C2 is enough to make the overall result unsatisfactory. Several C3 observations do not have the same effect.

That distinction matters when reviewing quotations. An unsatisfactory result does not mean every observation has equal urgency, and it does not automatically mean a full rewire or consumer unit replacement. The observation should identify the specific defect or condition. The full or partial rewire guide explains why the scale of work must follow the installation evidence rather than the headline result.

The report should also define what was inspected and tested. Concealed cables, locked rooms, inaccessible equipment or an agreed exclusion can limit the evidence. The home buyer EICR guide covers how to read the extent and limitations before relying on a report during a purchase.

Why the BS 7671 edition matters in October 2026

There is a temporary standards transition. The IET says BS 7671:2018+A4:2026 was published on 15 April 2026, while the previous Amendment 2 and Amendment 3 edition remains valid until 15 October 2026. During that six-month period, an inspector may work to either current edition. After 15 October, Amendment 4 is the edition to use.

The report declaration should state the edition and amendments used. This is particularly relevant to FI. The earlier model form uses “further investigation required without delay”. Amendment 4 changes the wording to “further investigation is advised” and makes clear that FI itself does not create an unsatisfactory outcome. The IET's 2026 explanation of the FI change says it is for a potential issue that could not be fully determined within the inspection's extent or limitations.

Do not remove the practical importance of FI because its wording has changed. The observation should still say what prompted concern, and the person ordering the report should ask what investigation is recommended and how soon. Landlords must also read the separate legal duties that apply to their property, covered later in this guide.

C1: danger present

C1 is the most serious classification. It means danger is present and people using the installation are at immediate risk. Electrical Safety First says the person ordering the report should be advised immediately, without waiting for the completed document. Action may involve making the condition safe, or switching off and isolating the affected part until it can be remedied.

Do not open a consumer unit, remove a fitting or try to prove the defect yourself. If the inspector has isolated a circuit or item, leave it isolated and follow the written safety advice. The eventual repair and certification depend on what was found. The guide to electrical certificates after installation work explains the different records that may follow completed remedial work.

C2: potentially dangerous

C2 means the observed condition was not an immediate danger at the time of inspection, but could become one if a fault or another foreseeable event occurred. Best Practice Guide 4 calls for urgent remedial action. It is not a softer version of C3, and it is one of the codes that makes the overall assessment unsatisfactory.

Ask for the observation in plain language, its location or circuit reference, and a separate scope for the remedial work. If the finding involves the distribution board, do not assume the only solution is a replacement board. The consumer unit upgrade guide sets out the installation evidence, circuit condition, earthing, bonding and protection that should inform a quotation.

C3: improvement recommended

C3 is used when the observation is not considered an immediate or potential danger, but an improvement would enhance electrical safety. It does not make the EICR unsatisfactory. An older installation may differ from the latest standard without automatically being unsafe, and Electrical Safety First's guidance explicitly warns against treating every difference as a reason for upgrading.

A C3 can still be useful planning information. If you are already renovating, changing a kitchen, adding circuits or preparing for a higher electrical load, it may be sensible to discuss the recommendation as part of that wider design. The lighting and power alterations service explains the information to assemble before a separate installation quotation.

Keep the language accurate when comparing proposals. A recommendation is not the same as required urgent remedial work. Ask each contractor to separate C1 and C2 items from optional C3 improvements so that price comparisons cover the same scope.

FI: further investigation

FI should be used when inspection or testing has exposed a potential safety issue but the inspector cannot determine the appropriate classification within the agreed extent or practical limitations of the EICR. It is not a general label for every unidentified fault. The IET says periodic inspection is not a fault-finding exercise, and Electrical Safety First says it should generally be possible to classify domestic observations without FI.

Ask three direct questions: what evidence prompted the FI, what part of the installation needs further investigation, and what access or testing is expected next? That turns a vague label into a defined instruction. If the issue is a live fault that needs diagnosis rather than a condition-report observation, the appropriate next step may instead sit within the electrician's agreed fault-finding scope. JI Electrical's current service overview lists the work offered without promising a diagnosis from report wording alone.

For a report produced before 15 October 2026, read the declared edition. Under the earlier current form, FI says investigation is required without delay. Under Amendment 4, it says investigation is advised. In both cases, it deserves a clear explanation. The code does not tell you the repair or price before the underlying issue is understood.

Why the observation list is not a repair quotation

An EICR is a factual report on the condition found at the time of inspection. Best Practice Guide 4 says an observation should describe the defect, damage or condition, rather than propose how to put it right. That separation protects the customer from jumping from a code to a product sale without a defined technical scope.

Before accepting remedial work, ask for:

1. The exact observation: code, location, circuit and report reference.
2. The proposed remedy: what will be repaired, replaced, tested or investigated.
3. The boundaries: exclusions, access assumptions and how additional defects will be handled.
4. The records: the appropriate certificate or written confirmation after the work.
5. The price basis: a clear quotation with VAT treatment and any separate investigation stated.

The seven checks before booking an electrician help compare written scope, changes and handover records. This is more useful than comparing totals when the contractors have priced different work.

Landlords have an additional legal timetable

For rented homes in England, do not use a general homeowner explanation as a substitute for the current rules. The government's electrical safety guidance for private and social rented sectors explains the report, copy, remedial and investigative duties. The underlying requirements are in the Electrical Safety Standards Regulations.

The government guidance current on 1 October 2026 says C1 or C2 requires remedial work and says landlords must ensure that identified further investigative work is carried out. It gives a maximum of 28 days, or a shorter period specified as necessary in the report. A C1 is an immediate safety issue, so a maximum legal deadline must never be read as permission to leave the danger in place.

Use the landlord EICR guide for the inspection cycle, report-copy duties and written confirmation after work. If the tenancy type or legal position is uncertain, obtain appropriate property or legal advice rather than asking the electrical report to answer a tenancy question.

A practical order for dealing with the report

1. Confirm the property address, inspection date and BS 7671 edition on the report.
2. Read the satisfactory or unsatisfactory assessment.
3. Match every code to its full observation and circuit reference.
4. Read the extent, agreed limitations and operational limitations.
5. Keep C1 and C2 work separate from C3 improvements.
6. Define any FI investigation before asking for a repair price.
7. Check the legal deadline if the property is rented or managed under a specific duty.
8. Obtain and retain the appropriate certification or written confirmation after work.

JI Electrical provides EICRs in Cirencester and the Cotswolds for homeowners, buyers, landlords and businesses. When enquiring, send the property type, reason for the inspection, occupancy, access details and any earlier EICR or electrical certificates. If you already have a report, send the complete document so the observations are read with their schedules and limitations.

Sources checked for this guide

• Electrical Safety First: Best Practice Guide 4, EICR classification codes
• IET: BS 7671 Amendment 4 transition period
• IET Wiring Matters: implications of Amendment 4 for FI
• IET: BS 7671 model EICR forms
• GOV.UK: electrical safety standards in rented sectors
• The Electrical Safety Standards Regulations 2020
• Electrical Safety First: periodic inspection and testing