The two kinds
- Physical nexus — offices, employees, contractors or inventory in a state. FBA stock in an Amazon warehouse counts.
- Economic nexus — crossing a sales threshold into the state, commonly $100,000 in sales or 200 transactions per year, with variations by state.
What nexus obligates you to do
Register for a permit, collect the right rate at checkout, and file returns on the state's schedule — including zero returns in many states. Marketplace facilitator laws shift collection to Amazon or Walmart for marketplace sales, but your own website's sales stay yours.
The trap
Nexus is retroactive: liability accrues from the moment you crossed the threshold, not from when you noticed. A nexus study answers where you stand in one pass.
Go deeper
Related reading
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