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Medicare Secondary Payer (MSP)

MSP is the term used to describe when another payer is responsible for paying a beneficiary's claims before Medicare pays.

Benefits Coordination & Recovery Contractor (BCRC), GHP - View crossover claim related information.

BCRC, NGHP - View when to contact the BCRC and what they are unable to assist with.

Billing MSP Electronically This link takes you to an external website. - View the Noridian Electronic Data Interchange (EDI) Support Services (EDISS) guide that illustrates how to properly submit a claim and reference the primary payer's information when submitting a claim to Medicare as the secondary payer.

Definitions - View definitions of MSP-specific terms

Form Locators - View form locators required for billing MSP claims.

Obligated to Accept Field (OTAF) - This is the amount the provider agreed to accept from the primary payer when the amount is less than the charges but higher than the payment amount; then a Medicare secondary payment is due to the provider. View details.

Payer Types - View the two-digit numeric values assigned to each MSP type and the description of each.

Payment Calculator - Providers may enter specific amounts from the primary insurance company's Explanation of Benefits in addition to their billed amount to determine Medicare's payment (line-level, not full claim billed amount).

Payment Calculation Examples - View examples of different primary EOBs and how to calculate specific fields that determine allowed amount, patient responsibility and Obligated to Accept Payment in Full (OTAF) amount for MSP claims.


  • Effective January 1, 2016, per CMS Change Request (CR) 8486, providers may submit, correct, adjust and cancel Part A MSP claims in DDE
  • Providers can enter up to 20 CARC codes and dollar amounts into DDE. Go to page three and then press PF11
  • For instructions on using the Claim Adjustment Segment (CAS) for Part A MSP CMS-1450 Paper Claims, DDE and 837 Institutional Claims Transactions, see CMS CR8486 This link takes you to an external website.


Last Updated Oct 23, 2017



Beneficiaries are required to complete a 30 month coordination period prior to Medicare becoming their primary insurance.