1. Prepare a CSV file that contains these fields. Email can be omitted if the Vendor record already has one. The Role added is the standard Vendor Centre role in NetSuite. Other role/s can be used.
2. Navigate to Setup > Company > Enable Features > Web Presence tab. Make sure that Vendor Access tab is set to True.
3. Navigate to Setup > Import/Export > Import CSV Records.
--Import Type = Relationships
--Record Type = Vendors
--Click Select and upload the CSV file
4. Set Data Handling to Update. Click Next.
5. Map the fields.
6. Click Next after mapping.
7. Enter an import map name. Click Save and Run.