Amendment 4 to BS 7671: What to Expect and How It Affects Your 18th Edition Qualification

Amendment 4 to BS 7671 — formally BS 7671:2018+A4:2026 — is the biggest regulatory event for UK electricians since Amendment 3. The new orange book was published in April 2026, and we’re now in the six-month crossover period before the Amendment 2/3 brown book is withdrawn for good.

 

If you’re studying for the 18th Edition exam, already qualified, or registered with a competent person scheme, this affects you. The good news: there’s no need for alarm. The changes are significant in a handful of specific areas, but for most electricians working diligently to Amendments 2 and 3, you’re already 90% of the way to compliance.

 

This guide covers the key dates, what’s actually changing, how exams are affected, and what your scheme provider will expect from you.

The Key Dates at a Glance

 

Date	What Happens
15 April 2026	Amendment 4 (orange book) becomes live
15 April – 15 October 2026	Six-month crossover — both A2/A3 and A4 are valid
15 October 2026	The A2/A3 brown book is withdrawn — all new work must comply with Amendment 4

 

Key point: The six-month parallel period exists for a reason — it gives contractors time to adapt to changes that affect their work, allows the industry to use up Amendment 3 stock, and gives training centres and exam bodies time to implement the changes.

 

How the Crossover Period Works

During the crossover, both books are active at the same time. Up to 15 April 2026, electricians and contractors had to use the brown book. From 15 April to 15 October 2026, its use is optional — work can be carried out to either the existing A2/A3 standard or the new A4 standard.

 

From 15 October 2026, only Amendment 4 is valid, and all new work must be completed to the new standard.

 

Exam tip: If you’re sitting the 2382 exam during the crossover period, confirm with your training centre which amendment your paper is based on before you book. Bringing an A4 book to an A3 exam (or vice versa) is a costly mistake — the question references won’t line up with your tabs.

 

Practically speaking, it makes sense to start working to the new amendment as soon as you can. Being up to speed with the regulations before October means the deadline passes without drama — and you won’t be caught out at your next scheme assessment.

 

Do You Need to Resit the 18th Edition Exam?

This is the question on everyone’s mind, and the answer is straightforward:

 

No. There is no requirement for anyone holding a valid 18th Edition certificate to resit the exam or attend an update course.

 

However, two caveats apply:

 

Consideration	Detail
Employer requirements	Some employers will send electrical staff on an update course as part of CPD requirements, and sometimes for insurance purposes
Professional duty	All electricians are expected to familiarise themselves with the changes and additions — especially those that affect their day-to-day work

 

Remember: “Not required to resit” is not the same as “not required to know.” If a change in Amendment 4 touches your area of work — battery storage, data cabling, medical locations — you’re expected to be working to it from October 2026.

 

How Exams and Courses Are Affected

If you started a course using the Amendment 2/3 brown book that overlaps with the introduction of Amendment 4, you will normally be allowed to complete your studies and sit the exam to Amendment 2/3 for several weeks after the changeover. After that, all exams move to the new Amendment 4 book.

 

The reassuring part: most of what you’ve learned from the brown book remains relevant in the orange book. The structure of BS 7671 — its 8 Parts, the regulation numbering system, the core protection principles in Part 4, the testing sequence in Part 6 — carries straight over. If you’ve been revising with our section-by-section revision breakdown, that foundation still stands.

 

The exam format itself is unchanged: 60 multiple-choice questions, 2 hours, open book. Our guide on how to pass the 18th Edition exam first time applies just as much under Amendment 4 — you’ll simply be tabbing an orange book instead of a brown one.

 

What Scheme Providers Will Expect

If you’re registered with NICEIC, NAPIT, or another competent person scheme, here’s what’s expected:

 

Requirement	Detail
Update your knowledge	By self-study or an update course — whichever suits your learning style
Show a valid A4 book	At your next assessment after you begin working to Amendment 4
Demonstrate awareness	Be fully aware of how the new regulations affect your specific work
Expect questions	Assessment officers will question you on the new regulations at your next annual assessment after you begin working to A4
Crossover flexibility	If you choose not to implement A4 immediately, you won’t be required to provide evidence — but from 15 October 2026, you must work to A4 and provide evidence as required

 

What’s Changing: The Five Main Areas

Until the industry has fully digested the new book, here’s the word on the wire — the five main areas of change, without going in too deep.

 

1. Functional Earthing and Functional Equipotential Bonding (ICT)

Amendment 4 brings clearer definitions relating to functional earthing, functional bonding, and earthing for EMC performance, applicable to ICT installations, data centres, and specialist installations. This is most relevant to commercial and industrial settings, where it will affect installation design and EICR coding at inspection and test.

 

2. Stationary Secondary Batteries — A New Chapter

A brand-new chapter covering batteries used for electrical storage and the supply of electrical installations. This is especially pertinent if you install solar storage or backup systems.

 

Area	What to Expect
Technologies covered	Lithium-ion, lead-acid, and other chemistries — new and old
Ventilation	More explicit rules on ventilation requirements
Fire separation	Separation from combustible materials; protection against thermal runaway
Location and access	Defined requirements for battery and cabinet positioning
Documentation	Clear labelling and essential documentation left with the person ordering the work

 

Important: Expect battery installs to become more like EV charger installs — more paperwork, an emphasis on defined zones, and enhanced scrutiny of fire safety.

 

3. Power over Ethernet (PoE) — A New Section

PoE is no longer just an afterthought on a network — Amendment 4 treats it as a power system in its own right, with:

 

• Specific requirements for cable ratings and maximum power classes
• Measures for heat generation in grouped or bundled cables — no more squeezing one last Cat 5 into overfilled trunking
• Thermal constraints to be considered, treated more like SELV and PELV
• Requirements for separation from low voltage circuits

 

4. Medical Locations — Major Revision of Section 710

Section 710 already exists, but it sees a major revision:

 

Change	Detail
Classification	Updated classification of medical locations
RCDs/RCBOs	Revised RCD and RCBO requirements
Supplementary bonding	New guidance, plus mandatory testing (see below)
UPS and IPS	More clarity on uninterruptible and isolated power supply systems

 

Even small clinics will need more rigorous paperwork and bonding checks.

 

5. Resistance of Supplementary Bonding Conductors — Measured, Not Assumed

This is a small but important change to inspection and testing. A new dedicated schedule of test results is introduced for measuring and recording the resistance of supplementary bonding conductors.

 

Key point: It will no longer be sufficient to look at supplementary bonding and record it as “present.” The effectiveness of the conductors cannot be assumed — they must be physically measured with a test meter and the actual values recorded on the new schedule.

 

If supplementary bonding is a weak spot in your revision, our guide on supplementary bonding and touch voltage covers when it’s required, where it goes, and why the resistance value matters.

 

How Amendment 4 Affects Domestic Installers

If your work is mainly domestic and you’re already complying diligently with Amendments 2 and 3, the impact is modest: some minor changes requiring small adjustments to working practices. You’re already 90% or more of the way to compliance.

 

The area of increased focus is documentation:

 

Documentation Area	What’s Expected
Labelling and identification	More emphasis on clear labelling throughout the installation
System documentation	Battery paperwork and PoE system details where fitted
Handover information	Enough information left with the owner so anyone following you can understand what was done, how the system is put together, and its safety functions
EICR implications	These requirements flow through to EICR coding on future inspections and tests

 

Exam tip: Documentation and certification questions are easy marks if you know the paperwork — and easy losses if you don’t. Expect Amendment 4 exams to probe the new schedules and labelling requirements, just as Amendment 2 exams leaned on the then-new AFDD and SPD rules.

 

Preparing for the Exam Under Amendment 4

Whether you’re sitting the exam to Amendment 3 during the transition window or to Amendment 4 afterwards, the fundamentals of preparation don’t change: learn the structure of the book, tab it properly, weight your study towards Parts 4 and 5, and take timed mock tests. If you’re unsure how long to allow, see our realistic study timeline guide.

 

For Amendment 4 specifically, give extra attention to:

 

• The new and revised sections — batteries, PoE, medical locations — as new material is a classic source of exam questions
• The testing changes — the supplementary bonding resistance schedule sits naturally alongside the Part 6 testing sequence
• Definitions — new and clarified terms around functional earthing and bonding will land in Part 2, and definitions underpin questions across the whole paper

 

Practice and Further Study

The best way to stay sharp through a regulation change is regular practice against the current standard. Test yourself across the key topics:

• Part 4 — Protection for Safety quiz
• Part 5 — Selection and Erection of Equipment quiz
• Part 6 — Inspection and Testing quiz
• Part 7 — Special Installations quiz

 

Our app includes 690+ practice questions covering all 8 parts of BS 7671 with detailed explanations referencing specific regulation numbers, plus full timed mock exams with the same weighted question distribution as the real paper — so when the exam moves to Amendment 4, your technique is already exam-ready.

 

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