Amendment 4 Transition Period - What You Can and Can’t Do Until October
Amendment 4 to BS 7671 was published on 15 April 2026. You can work to it today.
The previous edition is still valid too. That’s the part that catches people out.
For six months, two editions of the wiring regulations sit side by side. Both are current. Both are acceptable. But run them side by side without a plan and certificates start going out under the wrong standard.
Two Dates, Six Months Apart
15 April 2026 is when Amendment 4, the Orange Book, was published. It can be used from that date.
15 October 2026 is when the previous edition is withdrawn. Most people just call that one the Brown Book. Strictly, it’s the Brown Book plus the free Amendment 3 update that came after it.
The six months in between is the transition period. While it runs, both are recognised.
Two Standards, One Rule
Until 15 October you can certify work to either edition. A job designed and installed to the Brown Book can be certified to the Brown Book. A job done to Amendment 4 is certified to Amendment 4.
The rule is consistency within a project. One edition per job, start to finish. You can’t design to one edition, install to another, and certify to a third.
That holds at company level too. A firm can run one job on the Brown Book and the next on Amendment 4 in the same week. Both are valid. What you can’t do is mix the two editions in a single project.
On a job with one engineer, that takes care of itself. The risk shows up across a team, where different people pick up different parts of the same project at different times.
What Happens in October
After 15 October, the Brown Book is withdrawn. Amendment 4 becomes the only current edition of BS 7671.
From that date, new installations, additions and alterations are all certified to Amendment 4. Periodic inspection and testing is carried out to it as well. Scheme providers will expect you to be working to the Orange Book, and to have a copy when they assess you.
The transition window exists to let you finish jobs already running to the Brown Book. It isn’t there to put the switch off for six months.
How You Tell Which Edition a Certificate Used
Every certificate states which edition of BS 7671 it was issued to. So in theory, you check the certificate.
In practice, that line is a declaration. It tells you the edition the engineer meant to work to. It doesn’t prove the limits and checks behind the certificate match it.
An engineer who has used Brown Book values for years can put Amendment 4 on the form and still apply the old figures out of habit. The certificate reads as compliant. The work behind it says otherwise. A Qualified Supervisor only catches that by going back through the values, circuit by circuit.
The more engineers you run, the longer that takes.
What We’d Do
The transition window gives you flexibility. It doesn’t tell you to use it.
Running two editions side by side for six months means every engineer has to know which book each job belongs to, and the Qualified Supervisor has to police it across every certificate that comes in. That is a lot of room for error, spread over half a year.
The simpler approach is to switch the company over in one move. Finish the jobs already designed to the Brown Book under the Brown Book. Put everything new onto Amendment 4 (the Orange Book) from a set date. Pick the date, tell the team, and from then on there is one edition in use and nothing to track.
For most firms, that is less work and less risk than carrying two editions.
How Shine Forms Handles the Switch
Shine Forms applies the correct edition of BS 7671 for you. The regulation checks are verified directly against BS 7671 by Gary Gundry, who helped write it. When you enter test results, the software checks them against the right limits for the edition in use.
Switch a job to Amendment 4 and the checks switch with it. No old values slipping through out of habit. What the certificate declares and what the software checked are the same edition.
When Amendment 4 itself changes a value or a check, the software changes with it. Automatic. No extra cost. No waiting for an update.
Across a team, that means every engineer applies the same edition the same way. Whether they’ve been with you twenty years or twenty days.
For more on what changes on the paperwork itself, read How Amendment 4 Affects Your Certificates. For the two new chapters Amendment 4 adds, see Amendment 4 Introduces Two New Chapters.