Change separator when saving Excel file as CSV
When your save a workbook as a .csv file, Excel separates values with your default List separator. To force it to use a different delimiter, proceed with the following steps:
Click File > Options > Advanced.
Under Editing options, clear the Use system separators check box.
Change the default Decimal separator. As this will change the way decimal numbers are displayed in your worksheets, choose a different Thousands separator to avoid confusion.
Depending on which separator you wish to use, configure the settings in one of the following ways.
To convert Excel file to CSV semicolon delimited, set the default decimal separator to a comma. This will get Excel to use a semicolon for the List separator (CSV delimiter):
Set Decimal separator to comma (,)
Set Thousands separator to period (.)
To save Excel file as CSV comma delimited, set the decimal separator to a period (dot). This will make Excel use a comma for the List separator (CSV delimiter):
Set Decimal separator to period (.)
Set Thousands separator to comma (,)
If you want to change a CSV separator only for a specific file, then tick the Use system settings check box again after exporting your Excel workbook to CSV.