The only way to do it would be to use a change event macro.
With the workbook open press Alt+F11, this take you to the visual basic
editor.
In the left double click the worksheet where you want the code.
Past the following code.
Private Sub Worksheet_Change(ByVal Target As Range)
Dim r As Range
'Set range, so we are looking for text entered in A1:A500, change this as
needed.
Set r = Intersect(Range("A1:A5"), Target)
'If the change in the worksheet is not detected, exit the macro.
If r Is Nothing Then Exit Sub
'If text is entered do autofit on the column
Columns("A:A").EntireColumn.AutoFit
End Sub
