Modifier Requirements for Same Day Lab Tests

Some major payers, asking to use modifier 91 for CPT codes 80047-89398 when billing for more than one unit on a laboratory test for the same patient on the same day. For example, the modifier must be used when billing for repeat tests. Without the modifier, claims will be processed with only a single unit allowed and payments will be less than expected. Remittances will identify these payments with the Claim Adjustment Reason Code 97.