Solar · For traders
What did BS 7671 Amendment 4:2026 change for solar and battery installers?
Short answer
A4 was published on 15 April 2026 and replaces A3 for new work from 15 October 2026. It adds Chapter 57 for stationary batteries, requires PAS 63100 for dwelling installs, rewrites 551.7.1 to demand bidirectional-suitable protective devices, and splits 551.7.2. No official summary shows an 800 W plug-in solar section; plug-in legality comes from SI 2026/848.
Last checked 24 September 2026 · 2 sources
In more detail
- Other A4 changes: Section 545 functional earthing, 716 PoE, 710 medical, HRRB terminology.
- A3 (31 Jul 2024) had introduced 530.3.201 bidirectional/unidirectional devices.
- Secondary websites disagree on plug-in content - treat claims of a plug-in section as unverified.
The facts, dated
- 01BS 7671 A4 publication date — 2026-04-15 date
standard · UK · checked 24 September 2026 · IET
- 02BS 7671 A3 withdrawal date — 2026-10-15 date
standard · UK · checked 24 September 2026 · IET
- 03Regulation requiring PAS 63100 for batteries in dwellings — 570.6.7.203
standard · UK · checked 24 September 2026 · IET
Sources
- IET — www.theiet.org/media/press-releases/press-releases-2026/press-releases-2026-apri…
- IET — electrical.theiet.org/wiring-matters/years/2024/102-september-2024/the-impact-of…
Last checked: 24 September 2026