Do I need to collect sales tax in every state where I have customers?

No. Sales tax collection obligations are determined by nexus — a sufficient connection between the seller and a state — not by the location of every customer. An e-commerce seller is only required to collect and remit sales tax in states where they have established nexus. In states without nexus, customers are technically responsible for self-reporting use tax on their purchases, though this is rarely enforced at the individual consumer level.

Nexus can arise from physical presence (an office, warehouse, employees, or inventory stored in the state) or from economic activity. Following the Supreme Court's Wayfair decision in 2018, most states enacted economic nexus laws that require out-of-state sellers to collect sales tax once they exceed a threshold — typically $100,000 in sales or 200 transactions in the state in a calendar year. Five states have no general sales tax at all: Alaska (though some localities have local taxes), Delaware, Montana, New Hampshire, and Oregon.

Sales tax obligations are state-specific and triggered by economic nexus thresholds; income tax obligations arise from a different nexus analysis and are not directly tied to sales tax nexus. Sellers who have crossed economic nexus thresholds in multiple states face complex multi-state compliance requirements — registration, rate calculation, periodic filing, and remittance in each applicable state. Tax compliance software that integrates with Shopify can automate rate calculation, but nexus determination and registration decisions still require judgment and often professional guidance.

This is general tax information, not tax advice. Your situation may differ; consult a licensed CPA before making tax decisions.