On 15 January 2026, the Institution of Engineering and Technology (IET) and the British Standards Institution confirmed the publication of Amendment 4, 2026 to BS 7671:2018 IET Wiring Regulations, the UK standard for electrical installations. In broad terms, Amendment 4 reflects how electrical systems in buildings are evolving.
BS 7671 sets out the requirements for the design, installation, inspection, testing, and verification of electrical installations in the UK. It covers system design, protection and safety measures, equipment and wiring standards, specialist locations such as healthcare environments, inspection and testing procedures, and guidance for alterations and additions to existing installations. While BS 7671 is not law, it is widely recognised as the standard for compliance with the Electricity at Work Regulations and Building Regulations.
Amendment 4 will be published on 15 April 2026 and may be implemented immediately from that date. The current consolidated edition will be withdrawn six months later. This update reflects changes in technology, modern construction methods, and evolving expectations around electrical safety across residential, commercial, healthcare, and specialist environments.
Why This Matters
BS 7671 underpins how electrical installations are designed, installed, inspected, and tested throughout the UK. It applies to new low-voltage installations, as well as additions, alterations, and periodic inspection regimes on existing systems.
Electrical designers, installers, surveyors, and compliance teams should understand the changes introduced by Amendment 4 ahead of implementation to ensure ongoing safety, compliance, and confidence for clients and building users.
Key Changes Introduced by Amendment 4
Amendment 4 introduces several important updates that recognise emerging technologies and sector-specific risks.
A new dedicated chapter addresses stationary secondary batteries used for electrical storage and supply within installations, reflecting the rapid growth of energy storage systems linked to renewables, electric vehicle charging, and smart building technologies.
Functional earthing and equipotential bonding requirements have been introduced for information and communication technology systems, providing clearer guidance for safety and reliability in data-rich and digitally connected environments.
Power over Ethernet now has its own dedicated section, recognising the increasing use of PoE to supply power to lighting, sensors, access control systems, and other low-voltage devices, particularly within commercial buildings.
Section 710, which covers electrical installations in medical locations, has been significantly revised. Updates include a schedule for recording the resistance of supplementary protective equipotential bonding conductors, critical for safety management and compliance within healthcare settings.
Timing and Transition
From 15 April 2026, electrical works may be designed and installed in accordance with Amendment 4. Six months after publication, the previous consolidated edition will be withdrawn. This transition period allows organisations time to update procedures, training, and technical documentation.
Industry bodies and certification schemes are already preparing guidance, training, and technical support to help professionals adapt to the new requirements.
What This Means and Next Steps
At HJS part of the Ventro, we focus on delivering safe, compliant electrical services. Amendment 4 affects design, installation, inspection, testing, and reporting, especially in complex environments such as healthcare and large commercial estates. Our teams are preparing by reviewing available guidance, drafts, and industry summaries to understand how the changes may impact operations and update training and internal processes accordingly.
Electrical professionals should familiarise themselves with the standard once it has been published, review projects for any impact, and update relevant training. Amendment 4 reflects the evolving nature of electrical systems, and early preparation will support safer installations, stronger compliance, and better long-term outcomes for buildings and the people who use them.
Talk to Our Electrical Team
If you need guidance on what BS 7671:2018 Amendment 4, get in touch today and one of our specialists will advise you on the steps you need to take.