Providing your IOSS number to Shipstation ensures your shipments are handled appropriately.
Add Tax ID Numbers to International Settings
To add your Tax ID numbers to yourShipStationaccount:
1. Go toAccount Settings.
2. Select Shipping and then choose International Settings from the left-hand sidebar.
3. Click theAdd a Tax Identifier button.
4. Select the Tax ID type and Issuing Authority, then enter the ID number and give it a nickname (the nickname helps you identify the ID when selecting it for your shipments).
Available Tax ID Types:
TIN is a generic "Tax ID Number". Use this option if your Tax ID type is otherwise not provided in the list.
5. ClickSave Tax Identifier.
6. Click+ Add Another Tax Identifier to add additional Tax ID numbers.
Repeat until you have added all necessary Tax ID numbers toShipStation.
ShipStation will display a list of the Tax Identifiers that have been added. The Tax ID details cannot be modified once added. If you need to make a change to an entry, you must delete the entry and add a new one.
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