State Tax Nexus Calculator

This calculator checks whether your business has crossed a state's economic nexus threshold for sales tax, following the standard the U.S. Supreme Court set in South Dakota v. Wayfair, Inc., 585 U.S. 162 (2018): most states require you to collect sales tax once you exceed a dollar threshold in sales, a transaction count, or both. Target State is the biggest lever on the threshold-proximity outputs (Sales % of Threshold, Transactions % of Threshold, Sales Until Nexus, and Txn Remaining) because each state in the built-in table has its own threshold: nine of the twelve options here (Florida, Illinois, Pennsylvania, Ohio, Georgia, North Carolina, Washington, Colorado, and the "Other" catchall) use $100,000 in sales, several paired with a 200-transaction count, while California, Texas, and New York use a $500,000 sales threshold instead -- so switching states can move how close you are to nexus more than a real change in sales volume does.

Estimated Annual Sales Tax Liability is driven by that same threshold crossing: it's $0 below the selected state's nexus threshold and switches on once you cross it, so changing states near the threshold can swing this figure from zero to a real dollar amount. Once nexus is already established (sales above the threshold), though, Estimated Annual Sales Tax Liability moves linearly with Annual Sales in State at the selected state's tax rate -- sales volume, not the state pick, drives it from there. Sales Factor, in contrast, only responds to Annual Sales in State and Total Company Sales -- moved by both in roughly equal and opposite measure, since it's simply in-state sales divided by total sales -- and never to Target State. Separately, this calculator checks income-tax factor-presence nexus using a $50,000 property threshold, a $50,000 payroll threshold, a $500,000 sales threshold, or a 25% sales-factor threshold, and flags Income Tax Nexus if any one of the four is met, independent of the state-specific sales tax check. This model uses a simplified, fixed threshold table for a subset of states (Other defaults to the common $100,000/200-transaction Wayfair baseline) rather than looking up every state's actual current rule, some of which have changed since 2018.