Amendment 4 Lands on 15 October: Why Current Competence Is a Buyer's Risk Check

There is a date in the diary that matters more to the value of your electrical business than most owners have clocked. On 15 October 2026 the version of the wiring regulations that firms have worked to for years is withdrawn, and BS 7671 Amendment 4 becomes the standard everyone is measured against. This is one of the four themes in our September compliance-quarter briefing. Here I want to take the wiring-regs change on its own, because it quietly reshapes how a buyer reads your business.

First, a point that gets muddled on site and in the trade press. Amendment 4 is an amendment to the 18th Edition of BS 7671:2018, not a new edition. There is no 19th Edition. It was published on 15 April 2026, contractors have been able to work to it since, and it updates the standard in areas that have grown fast, including stationary battery storage, Power over Ethernet and medical locations. From 15 October, after a six-month transition, it is simply the definitive standard for compliant work.

Why a Withdrawal Date Becomes a Valuation Point

A good electrician was already working to the current standard before any deadline. So why does the date matter commercially? Because it changes how easily a buyer can prove your business is doing what it should. When someone acquires your firm, they acquire its compliance risk, and the cheapest way to reduce that risk is evidence that your team is demonstrably current.

A workforce whose competence is visibly up to date against Amendment 4 is one the buyer does not have to re-train, re-certify or worry about. A business still leaning on the withdrawn version after October hands the buyer a job to do, and a reason to trim the price. The 15 October line is really a line between two kinds of seller: the one whose currency is evidenced and filed, and the one who ends up scrambling to prove it under the pressure of due diligence.

A withdrawal date does not change what good electricians already do. It changes how easily a buyer can prove your business is doing it.

Registration Is Third-Party Assurance a Buyer Trusts

This is where scheme registration earns more than it looks. A NICEIC Approved Contractor is assessed every year, with work inspected, qualifications checked and insurance verified against BS 7671, now including Amendment 4. In effect, that annual assessment is an independent party continually restating that your business is current.

To an acquirer, that is one of the most credible and least expensive pieces of assurance in the whole file. It turns a claim you make about your own standards into something a third party has already checked. Registration that has been maintained and re-assessed year on year reads very differently from one that lapsed and was hurriedly renewed when a sale came into view.

What to Do With the Runway

September is the right month to act, because both versions of the standard are live until 15 October and the transition gives you a clean run at it. Get training records and competence evidence straightened out now, before and after the line, so the currency is banked rather than assembled in a hurry later. Keep registration and annual-assessment paperwork in order and filed where it can be produced in a day.

None of this is about passing an exam. It is about making sure the evidence a buyer will ask for already sits in a folder rather than in your head. Whether you sell next year or in three, a workforce that is plainly current against the standard of the day is one of the quiet things that holds a price together when the diligence team starts asking questions.