CO-17: requested information not provided.

What X12 says CARC 17 means

Requested information was not provided or was insufficient/incomplete.

CARC 17 · Start 01/01/1995, last modified 09/21/2008, stopped 07/01/2009 (retired).

X12 usage note: At least one Remark Code must be provided (may be comprised of either the Remittance Advice Remark Code or NCPDP Reject Reason Code.)

In plain terms: Requested information was not provided or was incomplete; X12 retired this code in 2009.

What it means on a remittance

The X12 list marks CARC 17 as stopped on 07/01/2009, so a current code list no longer treats it as active. It still shows up in old remittances and billing histories. Its X12 text requires at least one remark code, so the line should carry a remark that says what information was missing. For the same kind of problem today, compare CARC 16, whose X12 text is about claims that lack information or have submission or billing errors.

Typical causes

• The payer asked for records, a form or a detail and did not receive it.
• What was sent was incomplete or did not answer the request.
• The response went to the wrong address or claim number.
• The response arrived after the payer’s deadline.

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

What to check

1. Find the remark code on the same line; it should name the missing information.
2. Find the payer’s request letter or portal message and its deadline.
3. Confirm that what you sent answers each item and carries the claim number.
4. Check the date and method of your earlier response.

Correct, resubmit or appeal

Send exactly what the remark code or the request asks for, with the claim identifiers, by the method and deadline the payer states. Keep proof of when it was sent. If the information was already supplied, ask the payer to link it to the claim.

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 16 (claim lacks information), CARC 197 (authorization absent) and the full lookup.

Worked example (hypothetical)

An old remittance shows CO-17 with a remark asking for an operative report. The biller sends the report with the claim number to the payer’s records address and notes the date.

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.