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- X12 defines CARC 197 as precertification/authorization/notification/pre-treatment absent.
- No. 197 means the authorization is absent.
- For fee-for-service, the Florida Medicaid Behavior Analysis Services Coverage Policy requires authorization from the QIO before services start and at least every 180 days thereafter.
What CO-197 means
The X12 Claim Adjustment Reason Code list defines code 197 as "Precertification/authorization/notification/pre-treatment absent." The group code in front of it tells you who carries the adjustment. CO is Contractual Obligation: under your contract the amount cannot be billed to the family. In practice, a CO-197 on an ABA line means the payer could not match the service to an authorization it has on file.
ABA is almost always prior-authorized. In Florida Medicaid fee-for-service, for example, the coverage policy requires providers to obtain authorization from the quality improvement organization (QIO) before starting behavior analysis services and at least every 180 days after that (Coverage Policy section 7.2). Managed care plans run their own authorization processes, and since February 1, 2025, Florida behavior analysis claims for SMMC enrollees go to the recipient's plan.
Watch out. Do not resend the same claim. If anything was wrong, submit a corrected claim so the payer does not deny it as a duplicate.
CO-197 versus its neighbors
X12 has several authorization codes. Reading the exact one saves time, because each points to a different fix:
| CARC | X12 definition | Usual ABA cause |
|---|---|---|
| 197 | Precertification/authorization/notification/pre-treatment absent. | No auth on file for the member and date, or the auth number was left off the claim. |
| 198 | Precertification/notification/authorization/pre-treatment exceeded. | Units billed went past the authorized units for that code or period. |
| 284 | …number may be valid but does not apply to the billed services. | Auth covers 97153 but the line is 97155, or the modifier differs from the auth. |
| 296 | …number may be valid but does not apply to the provider. | Auth issued to a different billing or rendering provider, or a group or location mismatch. |
| 302 | …time limit has expired. | Date of service falls after the auth end date. |
Remark codes add detail. One that often appears beside authorization problems is RARC N54, "Claim information is inconsistent with pre-certified/authorized services."
The most common causes in ABA
- Dates outside the window. Sessions delivered after an authorization ended, or before the new one started, while a reauthorization was pending. With 180-day cycles, gaps happen at every renewal.
- Code or modifier not on the auth. The authorization lists specific procedure codes and sometimes modifiers. Depending on the payer's setup, a 97155 HN line may not match an auth written only for 97155.
- Missing or mistyped auth number. On the CMS-1500, the prior authorization number goes in item 23 (NUCC instruction manual), entered without hyphens or spaces. Transposed digits cause mismatches too.
- Provider mismatch. The auth was issued to one NPI and the claim was billed under another, or a new practitioner was added to the group but not to the plan's records.
- Wrong payer. The member changed plans, or the claim went to fee-for-service when it should have gone to the SMMC plan.
How to fix a CO-197
- Pull the authorization letter or portal record and compare it line by line with the denied claim: member ID, date range, procedure codes, modifiers, units, and the provider the auth was issued to.
- If the auth existed and matches, correct the claim (usually the auth number or provider identifier) and resubmit it as a corrected claim under the payer's rules.
- If no auth existed for those dates, ask the payer whether it accepts retroactive authorization requests and under what conditions. Many do not. Document the request either way.
- If the plan's records are wrong, open a ticket with the plan's provider services and keep the reference number with the claim.
How to stop it before you bill
Every cause above can be checked against data you already have before the claim leaves: the session date against the auth window, the code and modifier against the authorized services, the units billed so far against the authorized units, and the rendering provider against the provider on the auth. A pre-claim check that runs on each session note (date, duration, code, modifier, rendering practitioner) catches most CO-197s while they are still a scheduling problem rather than a write-off.
Whatever software you use, the pattern is the same: the claim is built from the session note, so most of these problems can be caught before the claim is submitted.
Tip. Read the RARC on the same remittance line. It often names the exact field or document the payer wants.
FAQ
What does CO-197 mean on an ABA claim?
X12 defines CARC 197 as precertification/authorization/notification/pre-treatment absent. With group code CO (Contractual Obligation), the payer found no matching authorization and the amount cannot be billed to the family.
Is CO-197 the same as CO-198?
No. 197 means the authorization is absent. 198 means the authorization was exceeded, for example more units billed than were authorized.
How often does Florida Medicaid require ABA reauthorization?
For fee-for-service, the Florida Medicaid Behavior Analysis Services Coverage Policy requires authorization from the QIO before services start and at least every 180 days thereafter. SMMC plans set their own authorization processes.
Where does the authorization number go on a paper claim?
Item 23 of the CMS-1500 (Prior Authorization Number), per the NUCC instruction manual.
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Related guides
Sources
- X12, Claim Adjustment Reason Codes
- X12, Claim Adjustment Group Codes
- X12, Remittance Advice Remark Codes
- AHCA, Florida Medicaid Behavior Analysis Services Coverage Policy (Dec 2024), incorporated in Rule 59G-4.125, F.A.C.
- AHCA, Behavior Analysis Services Information (SMMC transition, Feb 1, 2025)
- NUCC, 1500 Claim Form Reference Instruction Manual (v13, July 2025)
Last reviewed October 2026. This page summarizes public rules and vendor pages for education; it is not legal or billing advice. Payer contracts and plan manuals can add requirements, so confirm with the payer.