Below is the list of different statuses a PO can have and where it can move from these statuses.
Can be moved to
New PO is created, Products might be added or not added to the PO
Approved or Cancelled
Products were added to the PO and everything else looks good. PO is approved by the business.
Sent to Vendor or Acknowledged by Vendor or Cancelled
Sent to Vendor
When PO is sent to the Supplier
Acknowledged by Vendor or Cancelled
Acknowledged by Vendor
When the Supplier acknowledges the PO received from the business
Partial Goods Received or All Goods Received or Cancelled
Partial Goods Received
When all products are not received during the GRN process
All Goods Received or Posted to Accounts or Cancelled
All Goods Received
When all products are received during the GRN process.
Posted to Accounts or Closed or Cancelled
When the All goods are received from the PO it can be marked as closed.
This is the final status. Cannot go back or beyond this.