When Medicaid is the Secondary Payor

Billing insurance isn’t always simple, whether it’s formulary issues, step therapy or plan limitations, it’s common for a pharmacy to receive a rejection when trying to bill a patient’s insurance. For patients with Medicaid as secondary coverage, can you simply send the rejected claim to Medicaid? Caution should be exercised.    

Become an audit assistance member today to continue reading this article. As a member, you’ll have access to hundreds of articles and receive our monthly proactive newsletter!

Medicaid is typically referred to as the “the payor of last resort” because all options must be exhausted through a patient’s primary plan before submitting the full claim to Medicaid. Unfortunately, this isn’t as simple as identifying a primary claim that has rejected the prescription billed and then submitting the full claim to Medicaid so it will process. Pharmacies must first identify if this rejection can be resolved through the patient’s primary insurance (i.e., how would the pharmacy handle the claim if there was no secondary?). For example, if the primary payor is requiring prior authorization, that process must be sought either by receiving an approved prior authorization or a denied one (or changing the therapy to a covered drug product). Only then would it be appropriate to bill the patient’s Medicaid.

Be sure to utilize the Other Coverage Codes (OCC) appropriately. An OCC should be used when billing claims with multiple payors. This ensures the secondary payor reimburses the correct amount. Incorrect or inappropriate use of an OCC can lead to recoupments or even network termination if these errors are intentional. The codes below are typically recognized by third-party payors and used in NCPDP field 308-C8:

OCCDescription
2Other coverage exists/billed – payment collected
3Other coverage billed – claim not covered
4Other coverage exists – payment not collected
8Claim is billing for patient financial responsibility only (copay)

It is important to note that if a primary payor rejects a claim, the rejection codes are sent to the secondary payor. As previously mentioned, the first step when facing this predicament would be to resolve the coverage issue with the primary payor, whenever possible. Backing out of the claim and billing the secondary payor as primary may result in audit recoupment due to the secondary payor covering a cost that the primary payor might have paid. But what if OCC 3 is billed? The claim could still be at risk, as this depends on why exactly the primary insurance rejected the claim. Pharmacies should resolve primary payor rejections first by working through rejects like quantity limits, step therapy, formulary selections, or prior authorizations before billing the secondary payor.

PAAS Tips:

  • One exception to the rule is a multi-payor claim with conflicting coverage and reject code 606 indicating the payor prefers the brand/reference product.
  • Be sure to save denied prior authorization claims and document those denials on the prescriptions
  • Do not bill discount cards in place of primary insurance (in lieu of resolving primary insurance rejections).
  • Some copay cards and manufacturer coupons may accept reject codes due to formulary issues, but you must use the correct OCC.
  • Do not use a coupon or copay cards with a federal health benefits program, including Medicare, Medicaid, and TRICARE.
  • For more information regarding coupons, please see the July 2025 Newsline article: Manufacturer Coupons: Why It’s Important to Read the Fine Print

Heaven Bennett, CPhT