Economic nexus: why a big Q4 online sales month could owe another state your sales tax

Online orders tend to run heavier through Black Friday, Cyber Monday, and the weeks of holiday shopping right behind them than any other stretch of the year, and a lot of that volume lands through a website or marketplace rather than a booth. That's a good problem to have — until it quietly does something a vendor doesn't expect: push your total sales shipped into a particular state past the line where that state considers you a tax collector there, even though you've never set foot in it. That's called economic nexus, and the run-up to year-end is exactly when it's worth a few minutes of attention.

A different trigger than the one you've already heard about

If you've read a seller's-permit or sales-tax explainer aimed at Show vendors before, it probably covered physical-presence nexus — the way setting up a booth at a Market or Festival in another state can be enough, on its own, to require registering there, no sales threshold involved. Economic nexus is the other half of the picture, and it works differently: it's triggered purely by the dollar amount (and in some states, the number of orders) you ship into a state over a rolling period, with no physical presence required at all. A vendor who's never driven further than a neighboring county for a Show can still trigger it in a state three time zones away, purely through online orders shipped there.

This is the rule that came out of the Supreme Court's 2018 South Dakota v. Wayfair decision, which cleared the way for states to tax remote sellers based on sales volume instead of a physical footprint. Nearly every state with a sales tax has adopted some version of it since.

Why it's a running total, not a per-order reset

The part that catches vendors off guard is that economic nexus doesn't look at any single sale in isolation — it looks at your cumulative total shipped into that state, usually over the current or prior calendar year, and once you cross the line you're generally expected to register going forward (the specifics of exactly when registration kicks in vary by state). A $40 ornament order in July and a $90 one in September don't feel like a tax question on their own. The hundredth order of the year, shipped to the same state as the ninety-nine before it, can be the one that pushes the year's total past a threshold that was always quietly accumulating in the background. A strong Q4 is often what finally tips a state that was sitting just under the line all year — which is exactly why this is worth checking now, while there's still time to act on it before the year closes, rather than discovering it in January.

What the thresholds generally look like

The details here vary by state and change often enough that any specific number is worth double-checking rather than trusting at face value — but the general shape is worth knowing. Most states that have adopted an economic nexus rule use a dollar threshold somewhere in the neighborhood of $100,000 in sales delivered into that state over the relevant period, though a handful of states set a noticeably higher bar, and a few sit lower. Many states originally paired that dollar figure with a separate transaction-count test — commonly 200 orders — but a growing number of states have been dropping the transaction-count leg of the test in recent years and judging nexus on dollar volume alone. A state that still has a low transaction count on the books could, in theory, be triggered by a high volume of small orders even without much total revenue — which is part of why a clothing or jewelry maker running a brisk online shop might hit a transaction test before a furniture maker with the same total dollars does.

None of that is a rule you should apply to your own numbers from a blog post. A state department of revenue's own website is the only reliable source for its current threshold, and it's worth checking directly rather than relying on a secondhand table that may already be out of date.

The check worth running before December 31

A few concrete steps, in order:

• Pull a shipped-sales total by state for the year, not just a grand total. Most online sales platforms and payment processors can break this out; if yours can't natively, your order export usually has enough detail to sort it yourself.
• Compare each state's total against that state's current published threshold — not a number from memory or an older article, including this one.
• Pay attention to the states where you're already close, even if you haven't crossed yet. A state sitting at 70–80% of its threshold in October is the one a strong Black Friday and holiday push could tip over before the year ends.
• Remember that in-person Show sales count toward some states' totals too, depending on how that state defines its economic nexus base — it's not always an online-only calculation, so don't assume a big out-of-state Festival weekend is irrelevant to this math.
• If a state's total is close but under, recheck once more in early January once the full year's numbers are final, rather than assuming October's snapshot was the final word.

If you find you've crossed a line

Crossing an economic nexus threshold doesn't mean you did anything wrong — it means a state now expects you to register, start collecting its sales tax on orders shipped there, and file on whatever schedule it assigns you, usually starting from a specific date tied to when you crossed the line rather than retroactively from January 1. Most states' registration process is handled online and doesn't take long once you know you need it; the costly mistake isn't crossing the threshold, it's not noticing for a year or two and only finding out when a state follows up. If you're not sure whether your situation has actually crossed the line, or what to do once it has, that's a reasonable question to bring to a tax professional rather than work out alone from general guidance.

The takeaway

Economic nexus is a running total, not a per-sale event, and the same holiday sales surge that's good for a vendor's bottom line is also what tends to push a quietly accumulating state total over the edge. A few minutes spent sorting this year's shipped sales by state — before the year closes, not after the forms are due — is the difference between registering calmly on your own timeline and registering reactively because a state noticed first.

This article shares general information, not personalized tax or legal advice. Economic nexus thresholds, transaction tests, and registration rules are set individually by each state and change over time — confirm your current obligations with your state's department of revenue or a CPA or tax professional familiar with multi-state remote-seller rules before acting on any number here.

Seeing a full year of sales in one place — Shows and online orders alike — is most of the work of a nexus check already done, instead of a scramble through separate platforms in December. Artisans Almanac's 30-day free trial is worth a look before this year's numbers need sorting by state.