Bigseller now supports you to import an Excel file to bulk add the purchase orders.

Please follow steps below.
Step 1: Go to Purchase > Purchase Orders, click Import & Export > Import Purchase Orders, first download a Template file.

Step 2: Fill in this excel file as required then save it.

Step 3: Go back to the Purchase Orders page, click Import & Export > Import Purchase Orders, select a receiving warehouse first, then click to upload the saved excel file, and click Confirm to upload it.

Step 4: After the excel file is uploaded, the system will check the data then show the result. For example, "Successfully: 2 Failed: 1". 
Note: The content in one excel file can be partially imported to Bigseller. You need to edit the failed line according to the error message and import that line to Bigseller separately.