CO-27 Denial Code: Coverage Terminated Explained

The CO-27 denial code means the expenses were incurred after the patient's coverage had terminated — the plan you billed was no longer active on the date of service. It is an eligibility denial with a timing twist: the coverage may have been valid weeks earlier and lapsed before the visit, or the patient moved to a new plan you do not have on file. The resolution is finding the coverage that was active, not arguing with the plan that ended.

What is the CO-27 denial code? CO-27 is a Claim Adjustment Reason Code (CARC) indicating that expenses were incurred after the patient's coverage under the billed plan had terminated, so that plan is not responsible for the service.

Undeny's Take

CO-27 is a date problem. The plan is correct — it was not in force on the day of service — so disputing it directly goes nowhere. What usually happened is one of two things: the patient's coverage lapsed and they did not tell you, or they switched plans and your records still point at the old one. The recoverable path is to find the coverage that was active on that date and rebill it, and to re-verify eligibility on the actual date of service rather than relying on a check from a prior visit. The lesson CO-27 keeps teaching is that eligibility is true for a date, not forever.

What CO-27 Means

CO-27 indicates the service date fell after the patient's coverage under the billed plan ended. The plan is declining responsibility not because the service was wrong, but because the patient was no longer enrolled when it was rendered. Carried in the Contractual Obligation group, the amount is generally handled as a billing correction rather than immediately shifted to the patient, pending the search for active coverage.

Why the Coverage Was Inactive

The patient's plan terminated before the date of service and they remained enrolled elsewhere.
The patient changed insurers and your records still show the prior plan.
Coverage lapsed for non-payment of premium before the visit.
Employment or eligibility ended, closing the benefit on a date before the service.

How to Resolve a CO-27

Confirm the termination date the payer reports and compare it to the date of service.
Contact the patient to identify any coverage that was active on the service date.
Verify the active plan's eligibility for that date and rebill the correct payer following its filing rules.
If you have proof the billed coverage was in fact active on the date of service, dispute the termination with the appeal generator.

Related Eligibility Denials

CO-27 sits among the eligibility denials with PR-31 (patient cannot be identified as insured) and CO-22 (another payer is primary under coordination of benefits). Browse the full set under denial codes.

Frequently Asked Questions

What does CO-27 mean?

CO-27 means expenses were incurred after the patient's coverage terminated — the billed plan was no longer active on the date of service. The plan declines responsibility because the patient was not enrolled when the service was rendered.

How do I fix a CO-27 denial?

Confirm the termination date, contact the patient to find coverage that was active on the date of service, verify that plan's eligibility for the date, and rebill the correct payer. Disputing the terminated plan directly rarely works.

Can I bill the patient for a CO-27 denial?

Not immediately. As a Contractual Obligation adjustment, CO-27 is first handled by locating active coverage and rebilling. If no coverage was active and the patient was self-pay on that date, the balance may become the patient's responsibility under your financial policy.

How do I prevent CO-27 denials?

Re-verify eligibility on the actual date of service rather than relying on a check from a previous visit. Coverage is valid for a specific period, so a plan active last month may have terminated before today's appointment.

Informational only — not legal, medical, or billing advice. Always verify against current payer policy and the patient's eligibility on the date of service.

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