Navigate to Settings > Taxes and duties in your Shopify admin. Select United States from the Manage sales tax collection area. Click Collect sales tax under the Regions You’re Collecting In section. Decide which state or territory you are registered in.  Enter your sales tax ID in the appropriate field. Leave this form empty if you have applied for a sales tax ID but still need one. When you get your sales tax ID, you can update it. Optional: You can decide whether to charge tax on shipping if your company is based in a state with different shipping tax regulations. Select Advanced choices. Select whether or not you wish to apply shipping tax under that heading. Select Collect Sales Tax. Optional: Select Collect sales tax to add other areas and account numbers.