Amendment 4 Overview
BS 7671:2018+A4:2026 — published 15 April 2026, A2/A3 withdrawn 15 Oct 2026.
Status
A4 could be used from 15 April 2026. BS 7671:2018+A2:2022+A3:2024 was withdrawn on 15 October 2026, so A4 is now the only current version for new work, alterations, certification and periodic inspection. You must apply one edition in full — mixing clauses from different editions is not permitted.
Headline changes
New Chapter 57 (stationary secondary batteries); new section on functional earthing and functional equipotential bonding for ICT equipment; new Section 716 (Power over Ethernet); major revision of Section 710 (medical locations) with a new bonding test schedule.
Other affected areas
Definitions (Part 2), RCD type selection (531.3.3), surge protective device assemblies, rated current of switchgear assemblies (536.4.202), isolation and switching (537), LV generating sets (551), safety services (Chapter 56), swimming pools (702), marinas (709), outdoor lighting (714), EV charging (722), ring and radial final circuit arrangements (Appendix 15), energy efficiency (Chapter 81) and Appendices 1, 4, 6 and 13.