CO-13 denial code
The date of death precedes the date of service
How to fix it
Confirm the service date is correct. If the payer's record is wrong the patient's family or the payer must correct it before the claim can process.
How to prevent it
Rare, and usually a keying error on the service date. Check dates before appealing.
In practice
A claim for a routine follow-up returns CO-13, stating the payer holds a date of death earlier than the date of service. The patient attended the appointment and is very much alive.
Two things produce this. Either the service date was keyed wrong, which is the ordinary explanation and takes a moment to check, or the payer's file carries a date of death for the wrong person, which is rare and considerably harder.
Where the payer's record is at fault, no claim correction will help. The record has to be amended at the source, which for Medicare means the Social Security Administration rather than the contractor processing the claim, and that is a process the patient has to initiate.
What sits behind it
Check your own data before contacting anyone. Transposed digits in a service date are far more common than an erroneous death record, and confirming the encounter date against the schedule takes seconds where the alternative takes weeks.
When the payer's record genuinely is wrong, the patient's situation is much larger than a denied claim. An erroneous death record suspends benefits, stops Social Security payments and blocks care across every provider they see, so the practical service is telling them what has happened and where to go, not just working the denial.
For claims where the patient did die, the code is straightforward and the date is the whole question. Services on the date of death are payable; services after it are not, and a hospice or facility transition around that date is worth verifying before assuming the denial is an error.
Related codes
Terms used here — Eligibility Verification · Denial · CMS-1500
How we handle it — Eligibility Verification · Denial Management · Patient Support
Primary sources
The rules behind CO-13, at the bodies that publish them.
- Remittance Advice Remark Codes (RARC) (opens in a new tab)
X12 — The remark codes that qualify a CARC on an ERA. Reading the RARC is usually what tells you whether a denial is appealable.
- CMS-1500 claim form standards (opens in a new tab)
National Uniform Claim Committee — Maintainer of the CMS-1500 professional claim form and its data element definitions, plus the provider taxonomy code set.
- NPI Registry (NPPES) (opens in a new tab)
Centers for Medicare & Medicaid Services — Public lookup and management for National Provider Identifiers. A stale NPPES record is a quietly common cause of enrollment and claim rejections.
Looking for a different code? Search all 190 CARC and RARC codes
Questions about CO-13
Verify the date of service against your own schedule. A transposed or mistyped date is the usual explanation and can be confirmed immediately, whereas pursuing a correction to the payer's death record takes weeks and should only start once you have ruled the simple cause out.
Not through the claim or the payer's claims department. For Medicare the record originates with the Social Security Administration and must be corrected there by the individual, usually in person with identification. The claim can only be reprocessed after that correction propagates.
Generally yes — the restriction bites on services after the date, not on it. If the denial covers a same-day service, verify the date the payer holds before appealing, because the discrepancy may be in the record rather than in the rule.
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