When your company has 
nexus
 in the US or Canada, you might be required to collect sales tax or sellers use tax in those countries. You can establish nexus in a state or province in various ways. For example:
  • Your company has a physical presence in the US or Canada such as office space, warehouse space, paid staff, or inventory.
  • Your company sells a sufficiently large volume of goods in the US or Canada to have 
    economic
     nexus.
Each state and province has its own rules for determining nexus. Consult your tax advisor to determine where you have nexus.
IMPORTANT
In your tax calculation service request, specify the states in which you have nexus by populating the 
nexus
 or 
no_nexus
 API fields. When you do not include one of these fields in a tax calculation service request, the tax system makes its calculations as if you have nexus in every state.
For more information, see Step 1: Nexus.