I'd use a For..Next and a Select statement.

For ilN = 1 to Len(Activecell.value)

Select case mid(Activecell.value,ilN,1)
Case "1", "2", "3", "4", "5", "6", "7", "8", "9", "-"
' Do something.
Case Else
' Do something else.
End Select

Next ilN

I use this sort of thing all the time for stuff... Eg Stipping control
characters out.