TrailingZeroStart free

Economic nexus

Illinois economic nexus threshold

Illinois's economic nexus rule decides when out-of-state sellers must collect sales tax. Here's the current threshold, how it's measured, and how the transaction-count rule has changed.

By John DoeReviewed by Jane Doe, CPAUpdated June 2026How we verify
Sales threshold
$100,000
Transaction threshold
Removed
Logic
sales only
Measured over
preceding 12 months, evaluated quarterly on the last day of March, June, September, and December
Effective
October 2018

Source: Illinois Department of Revenue (IDOR)

Nexus & savings calculator

Estimate whether you still have nexus in Illinois — and what canceling could save.

$

Illinois no longer counts transactions — only sales matter here.

$
  • Physical presence
  • Sales over $100,000
  • Transactions (not counted here)
Likely eligible to cancel

Based on these numbers you likely no longer have nexus in Illinois. You can usually deregister after clearing the trailing-nexus window and filing your final return.

Trailing nexus: Illinois has limited or no trailing-nexus window — you can generally deregister once your nexus has ended and final returns are filed.

You could stop paying

$600/ yr

How to cancel in Illinois →

Estimate only — general education, not tax advice. Confirm with Illinois's tax authority before you register or deregister.

What is economic nexus in Illinois?

Economic nexus means you can owe sales tax in Illinois based purely on your sales volume there — no physical presence required. It traces to the 2018 South Dakota v. Wayfair decision. Illinois's threshold took effect October 2018.

Today the threshold is $100,000 in sales, measured over preceding 12 months, evaluated quarterly on the last day of March, June, September, and December.

The transaction-count history

Illinois used to trigger nexus at 200 transactions but removed that count in January 2026 — only the sales figure matters now.

That matters because the 200-transaction prong used to catch very small sellers — 200 orders can be just a few thousand dollars of sales. If transactions were the only reason you registered in Illinois, that trigger is gone.

What counts toward the threshold

cumulative gross receipts from sales of tangible personal property to Illinois purchasers; includes both taxable and exempt sales; marketplace-facilitated sales do NOT count toward the marketplace seller's own threshold when the facilitator is registered and collecting

Marketplace-facilitated sales do not count toward your own Illinois threshold.

Where TrailingZero fits

TrailingZero connects to your store read-only, maps where you actually have nexus state by state, and tracks your sales against Illinois's threshold so you register only when you truly cross it — and deregister when you fall below. During any wind-down it can file the zero-dollar returns so nothing lapses — and you only pay for the states you genuinely keep. Run a free audit anytime; this page is free education either way.

Illinois Economic nexus FAQ

What is the economic nexus threshold in Illinois?
$100,000 in sales, measured over preceding 12 months, evaluated quarterly on the last day of March, June, September, and December, in effect since October 2018.
Did Illinois remove the 200-transaction rule?
Illinois used to trigger nexus at 200 transactions but removed that count in January 2026 — only the sales figure matters now.
Do marketplace sales count toward economic nexus in Illinois?
No, facilitated sales don't count toward your own threshold.
Is this tax advice?
No. This page is general education built from public sources and the rules change often. Confirm your specific situation with the state's tax authority or your accountant before you register or deregister.

More on Illinois sales tax

See what you can stop paying in Illinois

Run a free audit and see which registrations you can drop — in minutes, no card required.

Start free →Free audit · no card required.

Other states

See all states →

Sources

Primary sources reviewed for this page. Data current as of June 2026.

TrailingZerois software, not a CPA or law firm, and this page is general education — not tax or legal advice. State rules and thresholds change frequently; confirm your situation with the state's tax authority or your accountant before you register or deregister. See how we research and review this data in our editorial & accuracy policy.