Trailing nexus
Trailing nexus in Colorado
"Trailing nexus" is the duty to keep filing in Colorado for a while after you drop below the threshold. Getting this window wrong is the single most common deregistration mistake — here's Colorado's rule.
- Has trailing nexus?
- Minimal / none
- Approx. duration
- —
- Can deregister below threshold?
- Yes, after the window
- Tax authority
- Colorado Department of Revenue — Taxation Division
Source: State rule
Colorado trailing nexus
Colorado has little or no formal trailing-nexus window — once your nexus ends and final returns are filed, you can generally deregister.
What trailing nexus means
When you drop below Colorado's threshold, the obligation doesn't end instantly. Most states make you keep the registration active and keep filing — even $0 returns — for a defined window. That window is "trailing" (or "sticky") nexus.
Colorado's trailing-nexus rule
Colorado does not have an explicitly codified trailing nexus rule. The economic nexus threshold is measured on a calendar-year basis: if a seller did not exceed $100,000 in the previous calendar year AND has not yet exceeded $100,000 in the current calendar year, nexus generally ceases and the seller may be eligible to close their account. There is no defined statutory period of continued obligation after dropping below the threshold.
Because Colorado uses a previous-or-current calendar year measurement, a seller who exceeded the threshold in Year 1 must continue collecting through the end of Year 2 even if Year 2 sales are low. In practice, deregistration is appropriate only when the seller is confident that both the prior full calendar year AND the current year-to-date are below $100,000. The seller must file a final return before submitting the account closure.
Why it matters for canceling
Canceling the day you drop below the threshold — or skipping a required final return — is exactly what triggers penalties. Clear Colorado's window first, file every return due during it, then close the account.
Where TrailingZero fits
TrailingZero connects to your store read-only, maps where you actually have nexus state by state, and computes Colorado's exact trailing-nexus end date so you cancel on the right day, not too early. 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.
Colorado Trailing nexus FAQ
- How long is trailing nexus in Colorado?
- Colorado has little or no formal trailing-nexus window.
- Can I stop filing in Colorado right after I drop below the threshold?
- In Colorado, once your nexus has ended and final returns are filed, you can generally stop.
- 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.
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Primary sources reviewed for this page. Data current as of June 2026.
- https://www.salestaxinstitute.com/resources/economic-nexus-state-guide
- https://www.salestaxinstitute.com/resources/colorado-to-require-remote-seller-sales-tax-collection
- https://www.salestaxinstitute.com/resources/colorado-sales-tax-return-filing-frequency-rule-change
- https://tax.colorado.gov/close-sales-tax-account
- https://tax.colorado.gov/DR1108
- https://tax.colorado.gov/sales-tax-account-license
- https://tax.colorado.gov/how-to-apply-for-a-colorado-sales-tax-license
- https://thetaxvalet.com/blog/how-to-cancel-your-sales-tax-permit
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.