What does denial code CO-197 mean?

CO-197 means the service required prior authorization and the payer has no valid authorization on file matching the claim. It is a contractual adjustment in most contracts, so the balance generally cannot be billed to the patient.

Can a CO-197 denial be appealed?

Yes, and a meaningful share succeed. The most common winning argument is that a valid authorization existed but was not matched to the claim because of a code, provider, or date-span mismatch. Retroactive authorization is also available from many payers within a short window for emergent services.

Can I bill the patient for a missing authorization?

Only with a signed advance notice of non-coverage executed before the service. Without it, most contracts require the provider to absorb the balance, because obtaining authorization is the provider's administrative responsibility.

CO-197: Precertification, authorization, or notification is absent

CO-197 is an administrative denial with a clinical remedy: the service may well have been necessary, but the payer was not asked in advance. Because most contracts make authorization the provider's obligation, this balance usually cannot be moved to the patient, which makes CO-197 one of the more costly preventable denials. A meaningful share are overturned on appeal when authorization actually existed but was not matched to the claim.

What it means: The service required prior authorization and the payer has no valid authorization on file for it.
Who pays the balance: Contractual in most contracts - failing to obtain authorization is the provider's administrative responsibility.
Group code CO: Contractual Obligation - the provider absorbs the balance and cannot bill the patient

Why CO-197 happens

No authorization was requested because the requirement was not known.
An authorization exists but the CPT code billed differs from the code authorized.
The authorization expired before the service was rendered, or the date of service fell outside the approved span.
The authorization was issued to a different rendering provider or facility than the one that performed the service.
The units or number of visits authorized were exceeded.
The service was emergent and the payer's retro-authorization window was missed.

How to fix a CO-197 denial

1
Check whether an authorization exists that simply was not matched
Search the payer portal by member and date rather than by authorization number. A surprising share of CO-197 denials involve a valid authorization under a slightly different code, provider, or date span - which is a much easier appeal than a missing one.
2
Request retroactive authorization where the payer permits it
Most payers allow retro-authorization within a defined window for emergent services or retroactive eligibility. That window is short and separate from the appeal deadline.
3
Appeal with the clinical record when the service was urgent
Where authorization could not reasonably have been obtained in advance, appeal on that basis and document the urgency contemporaneously from the record.
4
Do not bill the patient without a signed advance notice
Absent a signed waiver executed before the service, the write-off is contractual. Billing the patient for the practice's missed authorization is a contract violation.

Preventing CO-197 denials

Maintain a current prior-authorization requirement list per payer and check it at scheduling, not at the point of service.
Reconcile the authorized CPT codes against the codes actually billed before claim release.
Track authorization expiry dates and unit counts as actively as the authorizations themselves.

CO-197 frequently asked questions

What does denial code CO-197 mean?: CO-197 means the service required prior authorization and the payer has no valid authorization on file matching the claim. It is a contractual adjustment in most contracts, so the balance generally cannot be billed to the patient.
Can a CO-197 denial be appealed?: Yes, and a meaningful share succeed. The most common winning argument is that a valid authorization existed but was not matched to the claim because of a code, provider, or date-span mismatch. Retroactive authorization is also available from many payers within a short window for emergent services.
Can I bill the patient for a missing authorization?: Only with a signed advance notice of non-coverage executed before the service. Without it, most contracts require the provider to absorb the balance, because obtaining authorization is the provider's administrative responsibility.

Related denial codes

CO-50 PR-204 CO-16

Denial code explanations are original plain-English summaries written for reference and are not the official X12 code descriptions. Payer handling of any code varies by contract - always verify against the remittance advice and your payer agreement before adjusting a claim.