Serial Numbers

You can track serial numbers for sold and received items by using the Require Serial Number and Require Serial Number When Receiving Items add-ons (Tools -> Add-ons), which are available in the Corporate version.  

For items that need to have serial numbers assigned, you can turn on the setting labeled Require Serial Number in the Extras section when editing an item. Then when shipping and receiving this item, a serial number will need to be entered. You can then search for serial numbers in orders, invoices, and PO receipts. 

You can track ins and outs for serial numbers by using the report Inventory -> Reports -> Serial Number Activity. The report will show when the number was received, and when it was sold.