Electrical Installation Certificate Explained: EIC Vs EICR

Every new electrical installation in a property, whether it's a full rewire, a new circuit, or a consumer unit replacement, requires formal certification to confirm the work is safe and meets BS 7671 wiring regulations. That formal document is the Electrical Installation Certificate, and if you've recently had work done or you're planning a project, getting an electrical installation certificate explained properly matters more than most people realise.

The problem is that many property owners, landlords, and businesses across London confuse the EIC with its close relative, the EICR (Electrical Installation Condition Report). They sound similar, but they serve very different legal purposes and apply at different stages of an installation's life. Mixing them up can lead to compliance gaps that put tenants, occupants, and your legal standing at risk.

At Electrical Testing London, our engineers carry out both EIC and EICR work across residential and commercial properties every day. This article breaks down what an EIC actually covers, who needs one, and how it differs from an EICR, so you can be confident the right certificate is in place for your property.

What an electrical installation certificate is

An Electrical Installation Certificate (EIC) is a legal document that a qualified electrician must issue whenever they complete a new electrical installation or a significant alteration to an existing one. It confirms that the work has been designed, constructed, and tested to the standard set out in BS 7671 (the IET Wiring Regulations). Without it, you have no formal proof that the installation is safe or compliant.

What the document contains

The EIC is split into several distinct parts, each signed off by the relevant person responsible for that stage of the work. The design section records the installation's intended specification, while the construction section confirms that the work was carried out in line with that design. A third section, signed by the inspector, records the results of all the testing carried out before the installation was energised.

An EIC without completed test results is incomplete and carries no legal standing, regardless of who signed it.

Your copy of the document will also include a Schedule of Inspections and a Schedule of Test Results, which log the specific checks made on each circuit. These records are critical if you ever need to demonstrate compliance to a local authority, a building control officer, or your insurer. Keeping them with your property documents is essential.

Who issues an EIC

Only a competent person, registered with an approved scheme such as NICEIC or NAPIT, can issue a valid EIC. Part P of the Building Regulations requires that most domestic electrical work in England is either notified to building control or carried out by a registered competent person who can self-certify. For commercial properties, the same qualified engineer must sign each section of the certificate.

If someone offers to complete electrical work without issuing an EIC, that is a serious red flag. Ask to have the electrical installation certificate explained to you before work begins, because the certificate is not optional paperwork; it is the legal evidence that your installation is safe and that building regulations have been met.

EIC vs EICR and other electrical certificates

The EIC and the EICR are the two documents you will most commonly encounter when managing electrical compliance, but they are not interchangeable. Understanding the difference helps you avoid submitting the wrong paperwork to a local authority or insurer.

EIC vs EICR: the core difference

An EIC is issued after new work is completed, certifying that a fresh installation or alteration meets BS 7671. An EICR is a periodic inspection of an existing installation, assessing whether it remains safe and compliant after years of use.

If someone presents an EICR as proof of new installation work, that document does not satisfy your legal obligation under Building Regulations.

The two certificates also differ in who triggers them. A contractor issues an EIC on completion of the job, whereas you commission an EICR proactively, often to meet landlord regulations, a change of tenancy, or an insurer's requirement.

Other certificates you might encounter

A Minor Works Certificate (MWC) covers small additions to existing circuits, such as adding a socket to a ring final circuit. It is not appropriate for new circuits or complete rewires, both of which require a full EIC.

Getting the electrical installation certificate explained correctly for each project type prevents costly compliance gaps. A Domestic Electrical Installation Certificate is simply the standard EIC format used for residential properties, containing the same legally required sections as the commercial version.

When you need an EIC in the UK

An EIC is required whenever new electrical installation work is completed on a property in the UK. This covers a broader range of projects than most people assume, and understanding the trigger points helps you confirm whether your contractor is obligated to issue one.

New circuits and full rewires

If you commission a complete rewire or any new circuit added to your property, an EIC is legally required under Part P of the Building Regulations for domestic work. Commercial projects fall under separate but equivalent obligations, and any competent engineer completing the job must certify it.

Failing to obtain an EIC after a new installation means you cannot prove the work meets BS 7671, which can affect your insurance, your sale, and your legal liability.

Significant alterations to existing installations

Consumer unit replacements, additional circuits for EV chargers, and new circuits for outbuildings all require a full EIC rather than a Minor Works Certificate. Having the electrical installation certificate explained before work begins helps you confirm with your contractor which document applies to your specific project.

Here are the most common trigger points for an EIC:

• Full property rewires
• New consumer unit installations
• Addition of new circuits (kitchen, bathroom, outbuildings)
• EV charger circuit installation
• New lighting or power circuits in commercial premises

What an EIC covers and what to check

A valid EIC contains several key sections that together confirm the installation has been properly designed, built, and tested. Knowing what each part means helps you verify the document is complete and legally sound before you file it away.

The main sections of the document

Every EIC includes a declaration page, which records details of the installation, the registered contractor, and the applicable wiring regulations. Attached to this are the Schedule of Inspections and the Schedule of Test Results, which log every circuit that was tested and the measured values recorded during commissioning.

The three sections must each carry separate signatures from the designer, constructor, and inspector, even if the same person performed all three roles on a smaller job. An EIC missing its test schedules is not a complete certificate, and no building control officer or insurer will accept it as proof of compliance.

What to check when you receive your EIC

Getting the electrical installation certificate explained by your engineer at handover is the most reliable way to confirm the document is complete and valid. Before filing it away, check these key points:

• Property address is accurate and matches the property worked on
• All sections carry the relevant signatures from designer, constructor, and inspector
• The certificate was issued by a scheme-registered electrician
• The Schedule of Test Results covers every new circuit with no blank fields

A certificate without completed test results has no legal standing, regardless of who signed the declaration page.

What to do if you lack the right paperwork

If you bought a property, inherited one, or had electrical work completed years ago without formal documentation, you are not alone. Many London landlords and homeowners only discover missing certificates when a property sale, a new tenancy, or an insurer's requirement brings the issue to the surface. The right course of action depends on what work was done and how long ago it took place.

If you inherited a property or bought without certificates

An EICR is the most practical route forward when you cannot trace the original EIC for an installation. A qualified engineer inspects the existing system and confirms whether it remains safe and meets current standards.

An EICR commissioned by a registered electrician gives you documented evidence of the installation's current condition, which satisfies most insurers and local authority requirements.

Any remedial work identified in the report must be completed and signed off before the installation can be considered fully compliant.

If a contractor failed to issue an EIC

Contact the contractor directly and request the certificate, since they are legally obligated to provide one after completing new installation work. If they are unresponsive or no longer trading, a registered electrician can inspect the work and issue a new EIC if it meets BS 7671. Having the electrical installation certificate explained clearly at this stage helps you confirm exactly what documentation your property still needs.

Next steps for a safe, compliant property

Whether you need a new EIC after a rewire, a consumer unit replacement, or an EV charger installation, the most important step is confirming that a registered electrician issues the right certificate for the work completed. Getting the electrical installation certificate explained clearly at the start of any project saves you from chasing documentation later and protects your legal position with insurers, building control, and local authorities.

If your property already has an existing installation and you need to verify its current condition, an EICR gives you that documented assurance. Both certificates play a role at different stages of a property's life, and having both in order means you can demonstrate full compliance with confidence. If you are unsure which certificate applies to your situation or you want to arrange an inspection, request a quote from Electrical Testing London and our engineers will point you in the right direction.