The plan does not cover this service and the balance belongs to the patient.
Often overlaps with plan exclusions on therapies or supplies. The practice question is not the code, it is whether the patient knew before the visit that the service was not covered.
A plan excludes mechanical traction. The patient gets it anyway as part of a visit, the line denies PR-96, and the balance lands on the patient. Whether that balance is collectible with goodwill intact depends entirely on whether anyone told the patient before the visit that the service was not covered.
Eligibility results record service level exclusions, and the denial worklist moves PR-96 balances to patient responsibility automatically during ERA posting.
General information for billing teams, not legal or payer specific advice. CARC definitions belong to X12; payer policies vary and control. Verify against the payer contract before acting on any individual claim.