To add a PO number prefix, follow the instructions:

Step 1: Click Settings

Step 2: Click Company Info on the left navigation pane

Step 3: On the Purchase Order Settings section at the bottom, enter your preferred PO Number Prefix. For example, if you put OM as the prefix, OM will be added to the PO number every time a PO is generated. Thus, your first PO number will read as OM1000, instead of just 1000, which would be the case if the PO number prefix remains blank.

Step 4: Click Update