BS 7671:2018+A4:2026 will be the second, full consolidated amendment to the BS 7671:2018 18th Edition IET Wiring Regulations, which was first published in 2018, with BS 7671:2018+A1:2020 (Standalone) in 2020, BS 7671:2018+A2:2022 in 2022 and BS 7671:2018+A3:2024 (Standalone) in 2024.
Significant changes include:
• A new chapter on Stationary Secondary Batteries where the purpose is for electrical storage and supply of electrical installations
• A new section on Functional earthing and functional equipotential bonding for information and communication technology (ICT) equipment and systems
• A new section on Power over Ethernet (PoE)
• A major revision of Section 710 Medical Locations and the inclusion of a schedule of test results for recording the resistance of supplementary protective equipotential bonding conductors
Amendment 4 can be implemented immediately when published on 15 April 2026 and the previous version, BS 7671:2018+A2:2022+A3:2024, will be withdrawn six months later.
This essential update to the IET Wiring Regulations will form the UK national standard for:
• All new low voltage electrical installations
• Additions and alterations to existing installations
• Periodic inspection and testing of existing installations
NAPIT encourages all electrical professionals to ensure they become familiar with the changes when published.
Members of the committee responsible for the technical content of BS 7671, JPEL/64, are not permitted to release any further information before the publication date.
Mark Coles, Head of Technical Regulations at the IET, says, “The IET is the authority for electrical installations in the UK and ensures that the National Wiring Regulations Committee carefully considers all necessary updates to the Regulations to ensure they best meet the needs of the industry.
“The Amendment continues the thread of embracing new technologies and the inclusion of a new section on Stationary Secondary Batteries is an exciting step into the future of renewable sources of energy and their integration into our lives.
“Amendment 4 is an essential update to provide safe electrical installations in the UK and it is imperative that the industry is ready to work to this new amendment before BS 7671:2018+A2:2022+A3:2024 is withdrawn.”
Sebastiaan van Dort, Director – Energy & Sustainability at BSI, adds, “BSI is proud to jointly publish this vital standard with the IET at a time when the UK is accelerating towards its 2030 clean energy goals. BS 7671 underpins safe, modern electrical infrastructure – essential for delivering the electrification needed to meet net zero ambitions.”
Further changes are included throughout all parts of BS 7671:2018+A4:2026, including the incorporation of Amendment 3:2024 to BS 7671:2018 as part of the main document.
This Amendment sees the further adoption of CENELEC Harmonized Documents and IEC standards as the UK continues the inclusion of standards for new and developing technologies.
In preparation for the release of BS 7671:2018+A4:2026, NAPIT is ensuring it has everything members need to get up to speed with the amendment, including:
• Pre-orders for updated NAPIT and IET publications are available from the NAPIT shop from 2 February 2026.
• NAPIT hosting a range of CPD webinars to provide an overview of the amendment and what it means to its members. The webinars will take place on 19 May, 2 June, and 7 July at 6pm, with a live Q&A with JPEL Committee representatives Frank Bertie, Steve Humphries, and Andrew Duffen.
• NAPIT launching its new set of NAPIT EXPO Technical Roadshows with Amendment 4 CPD masterclasses in Southampton, Leeds, Bristol, and Coventry, starting April 2026 and open to all. Here, attendees have access to face-to-face technical training and membership advice, as well as free gifts, discounts, and refreshments.
Frank Bertie, Managing Director at NAPIT, (JPEL/64 member and deputy chair of Sub Committee A), comments, “This Amendment is an essential update and is the result of years of work by the JPEL/64 committee, the committee responsible for BS 7671, with which NAPIT have had strong representation on for over 25 years.
“It’s important that our electrical members keep up to date with the ever-changing technologies and ways of working to ensure they are working to the safest standards, and they can do that by viewing our webinars, attending our events and within our updated publications.”
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