Change a field's data type

1. If your table contains data, make a backup copy of the table before you change data types or field sizes.
   
   
2. Open the table in Design view.
   
   
3. Click the Data Type column of the field you want to change, click the arrow, and select the new data type.
   
   
4. Click Save on the toolbar.

Caution   If the data type conversion would result in lost values, Microsoft Access displays a message telling you that errors occurred during conversion before it actually saves the changes. Click Cancel to cancel the changes. Click OK to continue and save the changes anyway.

For more information on the consequences of changing a field's data type, click .

Note   In large tables, changing a data type might take a long time. If you want to cancel the conversion process at any point while it is running, press CTRL+BREAK, and then click OK.