Creating a Dated Backup File

Every time Mathew closes a workbook, he’d like to have Excel create a dated backup of that workbook, meaning that it is saved using a filename that includes the date. Thus, if he saves “AnyWorkbookName,” it would save not just under that name, but also under the name “AnyWorkbookName [Today’s Date & Time].” Mathew is sure this needs to be done with VBA, but he’s not sure how to go about it.

There are any number of macros that could be developed to perform this task. Most all of them are variations on a theme (so to speak), so for our purposes a single example should suffice.

The following macro will, just before closing the workbook, save the workbook with a date and time appended to the end of the filename.

Private Sub Workbook_BeforeClose(Cancel As Boolean)
    Dim sFileName As String
    Dim sDateTime As String

    With ThisWorkbook
        sDateTime = " (" & Format(Now, "yyyy-mm-dd hhmm") & ").xlsm"
        sFileName = Application.WorksheetFunction.Substitute _
          (.FullName, ".xlsm", sDateTime)
        .SaveCopyAs sFilename
    End With
End Sub

The macro puts together the date and time string into the sDateTime variable. This is then inserted into the workbook’s filename by using the SUBSTITUTE worksheet function. (The date/time string is effectively inserted just before the filename extension.) The macro assumes that the workbook is being saved as an XLSM file because it must contain macros-such as the macro to do this saving.

The macro should be placed in the ThisWorkbook module for the workbook. This ensures that it will execute just before the workbook is closed.

There are, as well, third-party add-ins which can perform this task. The following are a few that you may want to check out.

Excel uTIlities