CO-26 — Coverage Not in Effect on Date of Service (Termination)

Denial Identifier

• Primary CARC: CO-27 — "Expenses incurred after coverage terminated." Related: CO-26 — "Expenses incurred prior to coverage." (X12)
• Common RARCs: N30 (patient ineligible for this service), MA27, N130 (consult plan benefit documents/guidelines)
• Group code is typically CO but payer-dependent.

Plain-Language Meaning

• The payer's records show the patient's coverage ended before (CO-27) or had not started as of (CO-26) the date of service billed.

Why the Claim Was Denied

• Registration/Eligibility: coverage verification not performed close enough to the date of service; plan termination not caught before the visit
• Payer processing: retroactive termination or retroactive enrollment not yet reflected in the payer's real-time system at the time of the original eligibility check
• COB: patient moved to a new plan and the old plan was billed by mistake

Information the Biller Must Review

• Coverage effective and termination dates, date of service, real-time eligibility response, payer portal history, COB/other-payer information, patient's current insurance card.

What Needs to Be Corrected

• Claim correction: If the plan was actually active and the payer's termination date is wrong, request payer correction/reprocessing with proof of active coverage (e.g., enrollment letter).
• Upstream correction: If coverage truly ended before the date of service, the account moves to secondary payer billing, self-pay, or the retro-eligibility/COBRA process — not a claim data fix.

Resolution Workflow

• Verify coverage dates via real-time eligibility and payer portal for the specific date of service.
• Compare to claim submission.
• If payer data conflicts with proof of active coverage, contact payer with documentation (enrollment confirmation, COBRA election, retro-eligibility letter).
• If coverage genuinely lapsed, identify the correct payer (new plan, Medicaid retro- eligibility, self-pay) and rebill accordingly.
• Document the eligibility timeline.
• Escalate if a Medicaid or Medicare Advantage retroactive disenrollment/enrollment issue is involved.

Department Most Likely Responsible

• Resolves current claim: Registration/Patient Access, Billing. Prevents recurrence:
• Registration/Patient Access — eligibility verification timed close to the date of service, including for recurring/scheduled series of visits.

Prevention Control

• Real-time eligibility verification on the date of service (not only at initial scheduling); automated alerts for high-risk coverage-gap populations (Medicaid, Marketplace); COB data refresh at each visit.

Escalation Trigger

• Conflicting coverage-date information between payer systems; suspected retroactive Medicaid/MA disenrollment (see CMS timely filing exception categories, cross-reference D11); patient disputes termination.

Sample Scenario

• Scenario: Claim denied CO-27 for a visit two weeks after a plan's stated termination date.
• Finding: Patient enrolled in a new employer plan effective the same date; old plan correctly terminated coverage.
• Action: Claim rebilled to the new payer identified through updated registration/COB data.

Resolution path at a glance

AI Search Terms / Synonyms

• CO27; CO-27; CO26; coverage terminated; expenses incurred after coverage terminated; policy termination denial.

AI Answer Guardrail

• Verify the exact coverage effective/termination dates against the date of service using a real- time eligibility source before recommending patient billing or rebilling to another payer.

Sources

• X12 CARC list