Selling into several US states means reviewing several sets of sales-tax rules. A store's location, inventory, sales channels and destination sales all matter. This guide gives you a way to organize that review with your tax adviser; it does not determine an individual business's filing obligations.
Key takeaways
- Check physical presence and economic activity separately. Being below a sales threshold does not settle every nexus question.
- Use each state's definition of sales and measurement period. There is no single nationwide threshold.
- Separate marketplace sales from direct website sales, while checking which transactions count toward each state's threshold.
- Keep the rule, source date, calculation and resulting action together so the next review is repeatable.
Start with the business facts
Build a state-by-state record of your offices, employees, inventory locations, fulfilment arrangements and sales activity. Include facilities used by third parties, and ask your adviser which activities matter under each state's rules. Do not assume every warehouse arrangement receives identical treatment nationwide.
For example, California's guidance identifies both physical-presence activities and an economic threshold. Its threshold covers combined sales of tangible personal property delivered into California by the retailer and related persons exceeding $500,000 in the preceding or current calendar year. That is a California rule, not a template for other states.
Compare thresholds without losing the conditions
Record these fields for every state you review:
- Sales included: gross, retail or taxable sales; goods or services; and treatment of marketplace transactions.
- Measurement window: calendar year, rolling months or another defined period.
- Trigger: sales amount, transaction count, and whether multiple conditions are joined by “and” or “or.”
- Next action: registration and collection timing, with the state source supporting it.
- Review owner: the person responsible for checking changes and confirming the calculation.
New York's remote-seller guidance, for example, uses both receipts exceeding $500,000 and more than 100 sales of tangible personal property delivered into the state during the immediately preceding four sales-tax quarters. Those quarters are not simply a calendar year. Keep this example tied to its source and check the applicable rules before acting.
These two examples were checked on September 25, 2026. They illustrate why a generic “sales by state” dashboard needs interpretation, not just a threshold alert.
Separate marketplace and direct sales
A marketplace collecting tax on an order does not answer every question about your business's other sales. Keep marketplace reports and direct-store orders distinct, then reconcile both to your accounting records.
Under California's marketplace guidance, marketplace sales can count toward the economic threshold even when the facilitator handles the tax. A seller whose California sales are all facilitated by qualifying marketplace facilitators may not need to register; direct sales can change that analysis. Confirm the facts instead of assuming either “the marketplace covers everything” or “every marketplace seller must register.”
If you add a channel, include tax ownership in your distribution-channel review.
Turn the review into an operating routine
Use this suggested workflow with the person who owns your tax decisions:
- Export destination sales: retain order dates, delivery addresses, products, discounts, returns and channel identifiers.
- Reconcile the totals: explain differences between order value, refunds and the sales measure required by the state. GMV is a separate business metric, not automatically the right nexus calculation.
- Confirm registration and collection dates: have the applicable state guidance or your adviser support each decision before changing checkout settings.
- Test checkout: sample relevant destinations, products, exemptions and refunds after the approved configuration is applied.
- Assign filings and records: identify who files returns, checks marketplace reports and retains supporting documents for the applicable retention period.
- Review changes: revisit the record when inventory moves, employees join in new locations, channels launch or sales approach a state's threshold.
Software can help organize transactions and apply configured tax rules. Confirm which registration, filing and monitoring services your provider actually includes; a calculation feature alone does not establish that every task is covered.
Selling from outside the United States
Keep state sales-tax review separate from customs duties and other business taxes. Your fulfilment model, importer arrangements and US activities should be part of the discussion with advisers familiar with your business. Avoid treating a sales-tax registration decision as an answer to every cross-border obligation.
Add the review owner and next review date to your ecommerce launch checklist. The useful output is a documented decision for each relevant state, supported by the facts of your store.
