If you work with electrical installations, you’ve probably heard about Amendment 4 to the 18th Edition Wiring Regulations. But what does it actually mean in practice?
This guide breaks down the key changes to BS 7671 in a clear, straightforward way, so you know what to expect and how to stay compliant.
When does Amendment 4 come into force?
Amendment 4 takes effect on 15 April 2026 and can be implemented immediately.
There’s a 6-month transition period, after which the previous version will be withdrawn on 15 October 2026.
In simple terms:
- From April 2026 → you can follow Amendment 4
- From October 2026 → you must follow Amendment 4
Key changes in Amendment 4
Amendment 4 reflects how the electrical industry is evolving, particularly with new technologies and modern installation methods.
Here are some of the main updates:
Battery energy storage systems (BESS)
There’s now a dedicated section covering battery storage systems, increasingly used with renewable energy installations.
Why it matters:
Clearer guidance helps ensure safe installation and protection of energy storage systems.
Power over Ethernet (PoE)
A new section has been introduced for Power over Ethernet (PoE) systems.
Why it matters:
With more smart buildings and connected devices, electricians need to understand combined power/data systems.
ICT systems and earthing
New requirements around functional earthing and bonding for IT and communication systems.
Why it matters:
It clarifies the difference between safety earthing and system performance requirements.
Medical locations updates
Revisions have been made to installations in medical environments.
Why it matters:
There’s an increased focus on safety, reliability, and continuity of supply.
General updates and clarifications
There are also broader updates to inspection, testing, and existing installation requirements.
Why it matters:
Even standard electrical work may be affected, so it’s important to stay up to date.
Why Amendment 4 is important
Electrical installations are becoming more:
- Technology-driven
- Energy-efficient
- Integrated with smart systems
Amendment 4 ensures regulations keep pace with these changes—helping maintain safety, compliance, and performance across the industry.
How to prepare for Amendment 4
The transition period might seem generous but leaving it too late can create unnecessary risk.
Getting up to speed early helps you:
- Stay compliant with current regulations
- Avoid rework or installation issues
- Work confidently with new technologies
Stay up to date with 18th Edition training
One of the most effective ways to understand the changes in Amendment 4 is through structured training.
At Pragmatic Consulting Ltd, we offer City & Guilds accredited 18th Edition Wiring Regulations courses, designed to give you a clear understanding of the latest updates and how to apply them in real-world scenarios.
Whether you’re new to the 18th Edition or updating your existing qualification, our training helps you stay compliant and confident on site.
View our 18th Edition courses and upcoming dates to get started.
City & Guilds 2382-26 18th Edition Full Course (3 days)
City & Guilds 2382-26 18th Edition (1 Day Update including Exam)
City & Guilds 18th Edition Exam Only
Final thoughts
Amendment 4 is a significant update to the 18th Edition, reflecting the direction the industry is heading.
For electricians and engineers, staying current isn’t just about compliance—it’s about working safely, efficiently, and professionally in a changing environment.
