Medicare is a secondary payer when the beneficiary is covered by group insurance, Workers' Compensation, or if other third-party liability (no-fault, liability) applies. For detailed information on CMS's Medicare Secondary Payer guidelines, refer to the CGS web page:
CMS Guidelines and Resources for Medicare Secondary Payer (MSP).
The remittance file happens twice a month. It contains refused bills and updates to patient information as well as the physician’s pay statement and important updates to the MSP billing guide.