According to US sales tax laws, SPOD needs to charge sales tax in all states where SPOD is registered, on the goods delivered to the merchant’s customer in the merchant’s name. Sales tax varies by state, city or even district and the tax is always added on top of the product cost. Sales tax will only be visible on the invoice from SPOD to the merchant. The merchant needs to check whether they are able to charge their customers sales tax when they invoice. In some states, the merchant can provide SPOD with a sales tax exemption form so that SPOD need not charge the customer sales tax.