BS 7671 Amendment 3 and the 19th Edition: What Changed

Amendment 3 to BS 7671, the UK wiring regulations, was published on 31 July 2024 and came into effect the same day. It was a small, focused change about protective devices in properties where electricity can flow in both directions, such as homes with solar panels or battery storage. The 19th Edition, meanwhile, does not exist. As of October 2026 the current standard is BS 7671:2018+A4:2026, and no date for a 19th Edition has been announced.

This is a question we hear a lot. A landlord is told their consumer unit "doesn't meet the new regs" and wants to know if they're breaking the law. A homeowner reads about the 19th Edition online and puts off a rewire to wait for it. Both are working from half-true information, so let's set it out properly.

What BS 7671 is, in plain terms

BS 7671 is the national standard for electrical installations in the UK. It sets out how wiring, consumer units, earthing and protective devices should be designed, installed and tested, and it's published jointly by the IET and the British Standards Institution. It sits behind most of the electrical rules you've heard of: Part P of the building regulations for homes, and the inspection regime landlords have to follow.

Between full new editions, the standard gets updated by amendments. The 18th Edition arrived in 2018, then came Amendment 2 in 2022, Amendment 3 in 2024, and Amendment 4 in 2026. Each amendment folds into the same book, which is why you'll see the standard written as BS 7671:2018+A3:2024 or, now, BS 7671:2018+A4:2026.

Amendment 3: the 2024 change that caused the worry

According to Electrical Safety First, Amendment 3 of BS 7671 "comes into immediate effect" on 31 July 2024, and it "is limited to the addition of two new definitions within Part 2" plus one new regulation. That's it. No rewiring of the rulebook.

The two definitions are for bidirectional and unidirectional protective devices. A unidirectional device is one "where it is intended by the manufacturer that a source of supply is only connected to one defined set of connection terminals". A bidirectional one can be fed from either or both sets of terminals. The new regulation, 530.3.201, says that when you select and install protective devices, you have to use the right type for the job.

Why did this need saying? Because of what the industry calls prosumer installations. Older breakers and RCDs were designed on the assumption that power comes in one end from the grid and flows out to your circuits. Solar inverters, home batteries and vehicle-to-grid chargers can push power back the other way. On a circuit fed from both directions, a device designed for one-way flow can fail to disconnect properly when it should. Electrical Safety First points squarely at "circuits connecting solar PV inverters or battery electric storage systems (BESS) with a consumer unit/distribution board".

Here's the part that matters to you. If your home has no solar panels, no battery and no EV charger, Amendment 3 changed nothing about how your installation is judged. It's an instruction to the electrician designing new work, not a verdict on your existing board.

Where we are in October 2026: Amendment 4 takes over

The regs have moved on again since Amendment 3. NICEIC confirms that Amendment 4, officially BS 7671:2018+A4:2026, "was published on 15 April 2026", and that the previous version, BS 7671:2018+A2:2022+A3:2024, "will be withdrawn on 15 October 2026". Until that date both versions count as current, so electricians can work to either. From mid-October 2026, A4 is the standard.

Amendment 4 is a bigger update than Amendment 3. The changes most relevant to homes and small premises:

• A new chapter on stationary secondary batteries. Home battery storage has gone from niche to common, usually paired with solar, and the regs now cover it properly.
• A new section on Power over Ethernet (PoE). That's power delivered down network cabling, used for things like CCTV cameras, access control and some lighting.
• Functional earthing and bonding for ICT equipment, aimed at the kit in comms rooms and home offices.
• A major revision of Section 710 on medical locations, which matters to clinics, dentists and care settings rather than houses.

One Amendment 4 change is worth knowing about if you're booking an inspection. Under the old rules, an "FI" observation on an EICR, meaning further investigation required, left the overall report unsatisfactory until it was resolved. Under Amendment 4, FI observations "do not affect the overall outcome of the report". That changes how some borderline reports read.

So if an electrician talks about "the new regs" in late 2026, they mean the orange book, BS 7671:2018+A4:2026.

When is the 19th Edition coming out?

The honest answer is that nobody outside the IET and BSI knows, and they haven't announced anything. As of October 2026 there is no published draft, no consultation and no timetable for a 19th Edition. The IET's own updates page is where any announcement would land first, and it currently talks only about Amendment 4.

Full new editions have historically come roughly every ten years: the 17th Edition in 2008, the 18th in 2018. On that pattern the trade expects a 19th Edition around 2028 at the earliest, but treat that as an educated guess, not a schedule.

The practical point: don't put work off waiting for it. Work designed and certified to the current standard stays valid. A rewire done properly in 2026 does not become non-compliant the day a new edition appears, because the regulations are not retrospective.

"My electrician says my board doesn't meet the new regs. Is it unsafe?"

On that basis alone, almost certainly not. New editions and amendments apply to new work. An installation is designed to the edition in force at the time it went in, and a consumer unit fitted correctly in 2010 doesn't become dangerous because the book has moved on. If that were how it worked, every house in the country would fail every time the standard changed.

What actually happens is this. At your next EICR, the inspector assesses the installation against the current standard, then codes anything that doesn't match by how risky it genuinely is. C1 means danger present, C2 means potentially dangerous, and C3 means improvement recommended. A board that lacks something the current regs require on new work, surge protection say, usually attracts a C3 at worst, and a C3 doesn't fail the report. Our explainer on EICR codes C1, C2 and C3 goes through what each one means for you.

Where you should be careful is the phrase itself. "Doesn't meet the new regs" gets used loosely, sometimes honestly and sometimes as a lever to sell a board you don't need. Ask two questions: which regulation, and what code did it get on the report? If there is no report, that's the first job, not a new consumer unit.

All of that said, some older boards genuinely are past it. Rewirable fuse wire, no RCD protection on socket circuits, a scorched or cracked enclosure: those are age and condition problems, not edition problems, and they deserve attention whatever the current book says. Our post on working out if your fuse board is safe covers the signs.

What landlords have to do

For rented property in England, the law is already specific. Regulation 3 of the Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020 requires every landlord to have the installation "inspected and tested at regular intervals by a qualified person", defined as "at intervals of no more than 5 years". The standard the installation is measured against is the 18th Edition of the Wiring Regulations, BS 7671:2018, as amended.

None of that changed with Amendment 3, and it doesn't change with Amendment 4. Your duty is a valid, satisfactory EICR with any C1 or C2 issues put right, not a consumer unit that matches the newest book. The full picture for landlords, including who gets copies of the report and how long you have to complete remedial work, is in our guide to landlord electrical safety certificate requirements, and our EICR and electrical certificates service covers the inspection itself across London.

When an upgrade genuinely makes sense

There are times when a new consumer unit is the right spend, edition or no edition:

• No RCD protection anywhere on the board. This is the single biggest safety gap in older installations, and it's about shock protection, not paperwork.
• Rewirable fuse wire carriers. They still work, but they're slow to protect against some faults and they're well past their design life.
• You're adding solar, a battery or an EV charger. Any new circuit is designed to the current standard, which after Amendment 3 means thinking properly about bidirectional protection, and after Amendment 4 means the new battery rules too.
• The board is full. No spare ways for the new circuit you need means the upgrade conversation happens anyway.
• Repeated C2s on successive EICRs. At some point patching stops making sense.

A modern board also buys you things the old one never had: RCBO protection per circuit, surge protection, and arc fault detection devices where they're sensible. Our post on AFDDs and surge protection explains what those actually do, and our consumer unit upgrades service is where to start if yours is due.

Frequently asked questions

Is my consumer unit illegal because it doesn't meet the latest wiring regulations?

No. The wiring regulations are not retrospective, so an installation that met the standard when it was installed does not become illegal when the standard changes. It only gets judged against the current edition at inspection, and anything short of today's requirements is coded by risk, not automatically failed.

What is the difference between Amendment 3 and Amendment 4 to BS 7671?

Amendment 3, from July 2024, was a small change adding rules about bidirectional and unidirectional protective devices for systems like solar and battery storage. Amendment 4, published in April 2026, is a much larger update covering home batteries, Power over Ethernet, ICT earthing and medical locations, and it becomes the sole current version on 15 October 2026.

When will the 19th Edition wiring regulations be published?

There is no announced date. As of October 2026 the IET and BSI have published no draft or timetable, and the 18th Edition with Amendment 4 is the current standard. Based on the gap between the 17th and 18th Editions, around 2028 is the earliest sensible guess.

What does BS 7671:2018+A3:2024 actually mean?

It's the 18th Edition of the wiring regulations, published in 2018, with Amendment 3 from 2024 folded in. The "+A3:2024" suffix just tells you which amendments the copy includes. The current suffix, from October 2026, is +A4:2026.

Does an EICR check my home against the latest amendment?

Yes, the inspector assesses against the standard in force at the time of the inspection. But older features are coded by how dangerous they actually are, not by how new they are, so an older board that lacks a modern requirement typically gets a C3 recommendation rather than a failure.

What is a bidirectional protective device?

A breaker or similar device the manufacturer has designed to be fed from either direction. It matters where power can flow back towards the board, as it does with solar inverters, home batteries and vehicle-to-grid chargers, because a one-way device on such a circuit may not disconnect safely under fault conditions.

Been told your board doesn't meet the new regs and want a straight second opinion? Book an EICR with us or call 020 3653 2600. We'll tell you what your installation actually needs, and just as often, what it doesn't.