How to Manage Serial Nos. in ERPNext?

Serial nos. are the unique code assigned to each items. With serial nos. item detail and its location is tracked. Serial nos. is generally tagged for item which requires after sales services on it. Hence, businesses mention serial nos. in invoice based on which items delivery and warranty status is updated. In case of after sales service, company refers to serial no. to check invoice and purchase detail of that particular unit of an item.

Note: ERPNext doesn't have functionality to generated barcode for serial nos. Hence you will need to use third party application to manage generate barcode for serial nos.

Let's consider an example of company in sales of desktop and laptop computer. As there is warranty and after sales services provided on items they assign serial nos. on each unit they purchase or assemble.

Status of serial nos.

1. In store - Available for delivery / material issue. Updated when submit GRN or enter serial no. manually.
2. Delivered - Delivered to customer.  Updated when submit serial no.
3. Purchase return -  These are the serial nos. which are returned back to customer.
4. Not in use - Are the units which were define purchase receipt but then canceled due to some reasons. These are the serial nos. which becomes active if tagged in purchase receipt or material receipt again.

How to make item a serialized item?

Its defined in item master. In Item >> Inventory detail >> Has Serial no., selecting "yes" will make it serialized item.

How serial nos. get assigned to each unit of a item?


Serial nos. are assigned as soon as company acquires that item. The transaction made while receiving items are purchase receipt a.k.a GRN (in trading) and backflush (in production).


Let's consider a scenario when company places an order for 10 units of serial nos. and making a receipt for the same. When making purchase receipt, user will need to define serial nos. for serialized item based on receipt qty. If 10 qty of PC received, then user will enter / scan 10 serial nos. in serial no. column of that item.

Based on the serial nos. of items mentioned in purchase receipt, on submission system will created a unique serial no. record for each unit of an item. Also status for serial no. is set as as "in store" which will also reflect in stock level report.

Inventory of serialized item is tightly integrated with qty of serial nos. in warehouse. In stock level report for item in particular warehouse will be qty of serial nos. with status as "in store". So, if item A has 5 qty in warehouse X. It means that there are 5 serial no. for that item with status "In Store".

There are multiple possible actions which can be taken over serial no. in store. It can be delivered or issues for production (as raw-material).

Delivery Note:
When making delivery note of serialized item you will need to mention serial nos. equivalent to items quantity. On submitting delivery note serial nos. status will change to "Delivered". Also, based on days of warranty mentioned in item master, system will calculate exact warranty expiry dates starting from delivery date.

There could also occur a scenario where sales bom is created for an item. And one of the child item is serialized. In that case, in delivery note, sales bom item will be in main item table but that itself is not serialized item. And child item will be listed in packing details table. You will need to provide child items serial no. in packing details serial no. column.

Material issue:
In case of material issue you will need to provide serial nos. which will be consumed while manufacturing of finished good.