Thanks to various sites and official documentation, I had the understanding a UK Company (Registration) Number could be one of the three following formats.
- 8 numbers, 00000000
- 1 letter prefix followed by 7 numbers, A0000000
- 2 letter prefix followed by 6 numbers, AA000000
Recently, we’ve had a company come to us with the format AA00000A, and I’m unable to find documentation covering this single letter suffix format anywhere.
Folks are often pointed to the Uniform Resource Identifiers Customer Guide PDF which also, does not specify that this is a valid format. I found an HMRC document which lists some prefixes not described in the URI doc, but again, no suffixes. Having a quick look through the Companies House github hasn’t shone any light on this format either.
The only breadcrumb I’ve tracked down is from a github post for UK Company Number regex which suggests that the one letter suffix can be C,D,F,L or R.
Can you share the details of this format, and any other variations please?