Hi Paul,

there should also be a leading zero if the call is to a landline or
mobile number, so you could do this at the same time using this
formula:

="0"&LEFT(A1,4)&" "&TRIM(RIGHT(A1,LEN(A1)-4))

assuming your numbers start in A1. Copy this formula down as necessary
- the first 5 characters (including the 0) will be separated by a space
from the rest of the number.

If you have overseas numbers ("00") or DQ numbers, the formula would
need to be modified.

Personally, I think phone numbers should be treated as text - you are
not likely to want to do any arithmetic on them!

Hope this helps.

Pete