MSP Tertiary Claims

In a Medicare Secondary Payer (MSP) situation, Medicare uses the primary payers allowed and paid amounts to calculate the supplemental amount that may be paid by Medicare. In some cases, a beneficiary may be covered by more than one primary payer. Before Medicare can process a tertiary claim, the claim must be processed by the other payers. The allowed amount by both primary payers might differ.

Providers submit MSP claims and tertiary claims using Fiscal Intermediary Shared System (FISS) Direct Data Entry (DDE). Providers also have the option of filing electronically, via the 837I. Submit these types of claims to Medicare including all the required information in certain situations involving multiple payers.

How to Submit Tertiary Claims

If you determine more than one payer is primary

  • Submit claim to
    • Primary payer first, secondary payer next
    • Medicare as tertiary, etc. with correct billing codes
  • Do not bill primary payer(s) and Medicare simultaneously

MSP claims are calculated using payment information from 837I

  • Medicare uses primary payer’s adjustment amounts when processing MSP claims for payment
    • Explain why billed amount was not fully paid by primary payer
    • Include the appropriate value code based on the MSP files
    • Include Claim Adjustment Segments (CAS) segment from primary payer(s) remittance advice report (835 electronic remittance advice (ERA) or paper remittance
    • Claim Adjustment Group Code (CAGC) paired with Claim Adjustment Reason Codes (CARC) - (explains primary payer’s adjustments)
  • List of appropriate CARCs can be found at Washington Publishing Company - Electronic Data Interchange

See Education on Demand Tutorials for audio presentation on MSP Conditional Payments and Tertiary Claims.


Last Updated Mon, 19 Dec 2022 19:09:11 +0000