Colorado · Resale certificate rules
Does Colorado accept an out-of-state resale certificate?
No
A certificate carrying only another state's permit number will not support an exempt sale into Colorado. This is the rule that most often turns a portfolio a seller believes is clean into a deficiency at audit, because the certificate on file looks valid and is the wrong instrument for the destination.
The rules we hold for Colorado
- Out-of-state certificate accepted
- No
- Multistate Tax Commission form accepted
- No
- Streamlined Sales Tax member
- No
- Certificate expiry
- Does not expire on a fixed schedule
- Self-collecting local jurisdictions
- Yes
Last reviewed 2026-06-16. Rules change; verify against the state before relying on this for a filing.
What does a Colorado permit number have to look like?
Every certificate claiming exemption in Colorado is matched against this pattern:
^\d{8}-\d{4}$ Format is one of eight checks, not the whole of validation. A number in the right shape belonging to a permit that has been revoked still fails, and so does a form that is correctly numbered but unsigned, undated, or missing the reason for the exemption.
What this costs at audit
An auditor does not review every exempt sale. Under statute they examine a narrow test period, calculate the share of exempt sales without a valid certificate, and apply that error rate to your total exempt sales across the whole audit period (Tex. Tax Code § 111.0042; Cal. Rev. & Tax. Code § 6481). One wrong form in a sampled quarter becomes an assessment across years.
Producing the certificate afterwards is narrower than it sounds. Streamlined states allow 120 days after a request, Texas allows 90 days from written notice, and California will not treat a certificate obtained after billing as timely at all. Certificates have been disallowed for lateness alone, with buyers who were genuinely exempt.
See what you would owe in Colorado
Upload an export of your exempt sales and we will estimate the tax, penalty and interest state by state, using the rules above. No account needed, and your file is never saved.
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