Excel allows you to merge cells together in two ways: using the Merge and Center tool on the ribbon or toolbar, or by using the controls in the Alignment tab of the Format Cells dialog box. If you merge cells quite a bit, you might long for a shortcut that will merge whatever cells you've selected.

Unfortunately, Excel doesn't include such a shortcut. You can, however, create one using a macro. The following is a simple macro to merge whatever cells you've selected:

Sub MergeCells1()
    Selection.Merge
End Sub

After you create the macro, you can assign it to a keyboard shortcut and you are set to go. If you instead want a macro that is a shortcut for the Merge and Center tool, then you can use the following:

Sub MergeCells2()
    With Selection
        .HorizontalAlignment = xlCenter
        .Merge
    End With
End Sub