Sub FormatTéléphone()
For Each xCell In Range("A2:A20")
xCell.NumberFormat = "General"
xCell.Formula = xCell.Value
Select Case Len(xCell)
Case Is = 8 'Fixe
xCell.NumberFormat = "000""/""00"".""00"".""00"
Case Is = 9 'Gsm
xCell.NumberFormat = "0000""/""00"".""00"".""00"
End Select
Next xCell
End Sub