CO-14: date of birth follows the date of service.

What X12 says CARC 14 means

The date of birth follows the date of service.

CARC 14 · Start 01/01/1995.

In plain terms: The patient's date of birth is later than the date of service.

What it means on a remittance

The payer found that the patient’s date of birth is later than the date of service, which cannot be true for a real encounter. In most cases it is a keying error in one of the two dates. CARC 13 is the matching edit for a date of death before the date of service.

Typical causes

• The date of birth was keyed with the month and day swapped or the wrong year.
• The date of service was keyed wrongly.
• A newborn’s claim was billed with the mother’s details or before the baby was enrolled.
• The payer’s file holds a wrong date of birth.

These are common billing patterns, not a diagnosis of your claim. The remittance and the payer's policy decide.

What to check

1. Compare the date of birth with the insurance card and registration record.
2. Compare the date of service with the chart.
3. For a newborn, check how your payer wants the baby identified.
4. Confirm the patient, not the subscriber, is named in the patient field.

Correct, resubmit or appeal

Correct whichever date is wrong and resubmit. If the payer’s file holds a wrong date of birth, ask how it wants the correction and request reprocessing.

Medicare dates that apply

A Medicare redetermination request must be filed within 120 calendar days from the date a party receives the notice of the initial determination; receipt is presumed 5 calendar days after the notice date unless there is evidence to the contrary (42 CFR 405.942(a)), and a late request can be considered for good cause (405.942(b)). Other payers set their own appeal windows in the contract or plan documents, so read the notice for the date. The tool above runs the date math.

Related codes

X12 does not publish a table that pairs each code with remark codes; the payer picks the remark code and prints it beside the CARC on the same remittance line.

Other codes: CARC 13 (date of death before service), CARC 6 (procedure vs. age) and the full lookup.

Worked example (hypothetical)

A claim denies with CO-14. The date of birth was typed as 2026 instead of 2016. The biller fixes the year and resubmits.

Sources

• X12: Claim Adjustment Reason Codes — code text, usage notes and dates (list dated 10/30/2026, retrieved 2026-11-02)
• 42 CFR 405.942 — eCFR, current through 2026-10-29 (retrieved 2026-11-02)

Code descriptions are X12 copyrighted material, quoted here only for the codes on this page and linked to the owner. For the full lists, use X12. The X12 text and the Medicare rule above were read from these pages on November 2, 2026. Causes, checks and examples are general billing practice written for this page, not X12 content. Payers revise code lists, contracts and policies, so confirm anything that affects a claim or a deadline with the payer.