The 18th Edition Wiring Regulations have had their biggest update since 2018. Amendment 4 – BS 7671:2018+A4:2026, known as the “orange book” – was published on 15 April 2026 and becomes mandatory on 15 October 2026. Here is what has changed and what it means for electricians.
What is Amendment 4?
Amendment 4 consolidates all previous amendments (A1:2020, A2:2022 and A3:2024) into a single publication – the orange book – and adds major new requirements that reflect modern electrical installations: battery storage, smart and data infrastructure, and energy efficiency. These build on earlier 18th Edition requirements such as surge protection and RCD protection. These build on earlier 18th Edition requirements such as surge protection and RCD protection. It is the most comprehensive update since the 18th Edition was first published in 2018.
Key dates
- 15 April 2026 – Amendment 4 published; it can be used immediately.
- 15 October 2026 – the six-month transition period ends and Amendment 4 becomes the standard for all new design, installation and certification.
- 16 October 2026 – the previous City & Guilds 2382-22 exam is withdrawn and the new 2382-26 becomes the only assessment.
The main changes in Amendment 4
Chapter 57 – Stationary secondary batteries (battery storage)
A brand-new chapter setting out the requirements for stationary secondary batteries – the battery energy storage systems (BESS) increasingly installed alongside solar PV and EV charging. It covers their safe design and installation and reflects the rapid growth of home and commercial storage.
Section 716 – Power over Ethernet (PoE)
A new section covering the distribution of extra-low-voltage DC power over balanced data (Ethernet) cabling – now common in ICT installations, where a single cable carries both data and power.
Section 545 – Functional earthing and bonding for ICT
A new section dealing with functional earthing and functional equipotential bonding for information and communication technology equipment and systems.
Download your free information pack
Find out how you could train as a domestic gas and heat pump engineer with a free copy of our information pack.
Download information packSection 710 – Medical locations
A major revision of the medical locations section, including a new schedule of test results for recording the resistance of supplementary protective equipotential bonding conductors.
Chapter 81 – Energy efficiency
A new chapter focused on improving the energy efficiency of low-voltage electrical installations, reflecting the wider drive toward lower energy use and carbon reduction.
What it means for you
You will need the new orange book (BS 7671:2018+A4:2026). The older blue (2018) and brown (A2:2022) editions are now out of date and cannot be used in the 2382-26 exam.
New candidates sit the City & Guilds 2382-26 exam. If you already hold the 18th Edition (2382-18 or 2382-22), you can get current quickly with our 1-Day Amendment 4 Update course.
Ready to train on the current standard? Book the full 18th Edition (2382-26) course.
Become a qualified gas engineer
Our New Entrant Gas Engineer courses take you from beginner to Gas Safe registered, with hands-on training and the ACS qualifications employers look for.
Blog categories
Keep up to date with the latest news from
Skills training group.