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CARC 228 · CO-228

CARC 228 Denial: Denied for failure of this provider, payer or subscriber to supply requested in… — How to Fix and Appeal

Reviewed by QuickIntell RCM Editorial Team · Last reviewed

Updated

TL;DR

CARC 228 (X12 Denied for failure of this provider, payer or subscriber to supply requested information to a previous payer…). CARC 228 denies because a previous payer requested information that was not supplied, blocking coordination-of-benefits processing.

Official X12 description

“Denied for failure of this provider, payer or subscriber to supply requested information to a previous payer for their adjudication.”

Source: X12 Claim Adjustment Reason Codes. The X12 External Code Lists are the single authoritative source for every CARC descriptor — always verify against the current release before building a claim-scrub rule.

What CARC 228 actually means

CARC 228 denies because a previous payer requested information that was not supplied, blocking coordination-of-benefits processing. Identify the prior payer, provide the missing information, and resubmit the COB chain.

Common root causes

  • Prior payer's information request (COB data, primary EOB) unanswered.

Prevention checklist

  • COB workflow that tracks prior-payer requests with due dates.

Appeal strategy — step by step

Most CARC 228 denials clear faster with the right remediation than with a formal appeal. Work the steps in order and escalate only when a lower-effort path has been ruled out.

  1. 1Supply the requested information to the prior payer, then resubmit the downstream claim.
Sample appeal-letter language for CARC 228
[Provider letterhead] Re: Appeal of CARC 228 — Claim #{claim_number} Member: {member_name} · Member ID: {member_id} Date(s) of Service: {dos} On {remittance_date} this claim was adjusted with CARC 228: "Denied for failure of this provider, payer or subscriber to supply requested information to a previous payer for their adjudication." We respectfully request reconsideration. The X12 External Code List definition of CARC 228 does not apply to this claim for the following reasons: 1. [Cite the clinical / coding / policy fact that rebuts the adjustment] 2. [Cite the supporting documentation attached — op note, EOB, LCD/NCD citation, NCCI edit indicator, modifier rationale] 3. [Cite the payer's own policy where applicable] Attached: {list supporting documents} Please process payment under the member's benefits. If additional information is required, contact the billing office at {provider_phone} or {provider_email}. Sincerely, {billing_manager_name}, {credentials}

Edit the bracketed fields before sending. This template is a starting point; a payer-specific appeal form may still be required — check the provider portal first.

Payer-specific notes

Payer-specific behavior for CARC 228 publishes here as the QuickIntell anonymized denial ETL ingests sufficient volume. In the meantime, consult the payer directory for the relevant provider manual and appeal form.

How common is CARC 228?

Search demand rank
#215

Out of 306 seeded CARCs, ranked by combined US monthly search volume for "CARC 228", "CO-228 denial", and "denial code 228".

Platform frequency
Pending ETL

Platform frequency ranks publish once the anonymized denial-rate pipeline reaches the publication threshold (strategy §12 Phase 2).

How QuickRCM prevents CARC 228

QuickRCM catches the root causes above before the 837 leaves the clearinghouse:

  • Claim-scrub rules fire on every root cause listed above — the scrub references the same X12 CAS segment logic that drives the denial, so what the payer checks, QuickRCM checks first.
  • When a denial lands, QuickRCM routes it to the correct worker with the documentation bundle already attached (op note, LCD citation, modifier rationale, EOB, primary 835).
  • Appeal templates tuned to each CARC (including this one) pull the supporting facts from the claim and fill the bracketed fields automatically.
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Frequently asked questions — CARC 228

What does CARC 228 mean?

CARC 228 is an X12 Claim Adjustment Reason Code. The official definition is: "Denied for failure of this provider, payer or subscriber to supply requested information to a previous payer for their adjudication." In plain English, the payer is telling you cARC 228 denies because a previous payer requested information that was not supplied, blocking coordination-of-benefits processing. Identify the prior payer, provide the missing information, and resubmit the COB chain.

How do I resolve a CARC 228 (CO-228) denial?

Start with the most common root cause: Prior payer's information request (COB data, primary EOB) unanswered. First step: Supply the requested information to the prior payer, then resubmit the downstream claim. See the full remediation and appeal checklist on this page before filing a formal appeal.

Is CARC 228 patient responsibility?

No — CARC 228 is typically carried under CO (Contractual Obligation) or OA (Other Adjustment), which means it is the provider's responsibility, not the patient's. Do not bill the patient unless the 835 CAS group code is PR.

What does CARC 228 look like on an EOB or 835 remittance?

On the 835 ERA, CARC 228 appears in Loop 2110 CAS segment as "CAS*CO*228*{amount}". On a paper EOB the same code prints in the Adjustment/Denial Reason column with the X12 description: "Denied for failure of this provider, payer or subscriber to supply requested information to a previous payer for their…" — usually paired with one or more RARC remark codes in the same remittance line for additional context.

Which RARC is paired with CARC 228?

CARC 228 is commonly observed with RARC N19. The RARC narrows the reason — for example, pointing at a missing modifier, an LCD citation, or a specific policy. Fix the underlying CARC first; the RARC usually clears with the corrected claim.

Disclaimer

This page is operational reference for medical-billing professionals. It is not legal, clinical, or contractual advice. X12 code descriptors are maintained by the X12 External Code Lists; always verify against the current X12 release and the payer's own published policy before submitting or appealing a claim.