18th Edition Wiring Regulations Amendment 4

18th Edition Requirements for Electrical Installations BS 7671- IET Wiring Regulations Amendment 4

What is it?

As the UK’s national standard for electrical installations, BS 7671 has requirements for all low voltage electrical installations, and helps professionals stay ahead of the curve with guidance on emerging technologies, modern practices and compliance requirements.

Whether you're working with solar photovoltaic (PV) installations, battery storage, Power over Ethernet or on medical locations, BS 7671 has the requirements for today’s electrical installation work. It’s not just about safety; it’s about competency and being up to date with current requirements.

The IET co-publishes BS 7671 with the British Standards Institution (BSI) and leads the UK’s national Wiring Regulations committee, JPEL/64, ensuring the standard reflects both international developments and UK-specific needs.

The current regulations, Amendment 3:2024 to BS 7671:2018 IET Wiring Regulations (the Brown Book) is still in use, and will be until 15 October 2026.

Amendment 4 will then become the definitive British Standard for all new low-voltage electrical installations, modifications to existing systems, and periodic inspection and testing.

When is the new amendment released?

Amendment 4:2026 to BS 7671:2018 IET Wiring Regulations (the Orange Book) is released on Wednesday 15th April 2026.

Is there a changeover period?

There is a 6-month changeover period from the date of publication (15th April), where you can continue to use the older Brown Book, or start to use the new Orange Book. The Brown Book can still be used until 15 October 2026.

What's changed?

This is amendment four to BS7671:2018; four areas have been added or updated from Amendment 3.

• Chapter 57 Stationary secondary batteries, where the purpose is for electrical storage and supply of electrical installations. 

• Section 545 Functional earth and functional sequential bonding for information and communication technology (ICT) equipment and systems.

• Section 716 Power over Ethernet (PoE)

• Revision to Section 710 Medical locations and the inclusion of a schedule of test results for recording the resistance of supplementary protective equipotential bonding conductors.

Do I need to update my current 18th Edition qualification to Amendment 4?

While you are not required to update your qualifications due to amendments, industry practice is to stay current with changes and amendments, and to revisit the qualification when the 19th Edition is released.

Competent Person schemes such as NAPIT and NICEIC electrotechnical scheme rules require certified persons/businesses to have documentation appropriate to the range and scale of electrical work undertaken, including the current edition of BS 7671 and amendments to BS 7671. Amendment 4:2026 can be implemented immediately after its publication on 15 April 2026, previous version will remain current for six months until withdrawn on 15 October 2026. From 15 October, your business will need to demonstrate access to a copy of Amendment 4:2026 to maintain your NICEIC or NAPIT certification.

ECS requires a recognised and up-to-date BS7671 certificate for Registered Electrician status. Registered Electrician status recognises those who are not only qualified to the industry-recognised Level 3 standard, but also have opted into a Code of Professional Conduct and a commitment to undertake CPD, including keeping up to date with the Wiring Regulations.