I've always seen it with the leading zero part of the area code to make 4, then 3 then 4 grouping. The leading zero was always listed. e.g. 0123 456 7890 and

I've always seen it with the leading zero part of the area code to make 4, then 3 then 4 grouping. The leading zero was always listed. e.g. 0123 456 7890 and 01/02 prefixes are landlines, 07 are mobile phones, 08 free, and 09 premium rate lines. Wikipedia [0] says that there are 8 digit local numbers, and 2/5 digit area codes, but I happen not to have lived in a place that uses them until mobile phones took over anyway. [0] https://en.wikipedia.org/wiki/List_of_dialling_codes_in_the_United_Kingdom https://en.wikipedia.org/wiki/List_of_dialling_codes_in_the_...