Calculation of Deductible and Coinsurance

40.8.6.2 - Calculation of Deductible and Coinsurance (Rev. 11550; Issued: 08-12-22; Effective: 10-13-22; Implementation:10-13-22) The A/B MAC (Part A) calculates deductible and coinsurance in the usual manner after applying the primary payer's payment allocated for non-lab services. See examples below for calculation of coinsurance. EXAMPLE 1: Deductible Previously Met Outpatient services were furnished to a Medicare beneficiary for whom the provider billed $100 for lab services and $200 for emergency room services. The lab fee schedule amount for the $100 lab services is $70. The beneficiary's Part B deductible was previously met. The primary payer paid $150 for Medicare covered services without designating what portion of its payment was for each type of service. Since the ratio of lab charges to non-lab charges is $100/$200, the A/B MAC (Part A) divides the primary payer's payment of $150 into two amounts based upon the same ratio: $100/$200 = $50/$100. It applies $50 of the primary payer's payment to the $70 lab fee schedule amount and the remaining $100 to the $200 in non-lab charges (emergency room services). It calculates the coinsurance in the usual manner based upon the $200 non-lab charges. It does not charge coinsurance since the primary payment of $100 allocated to non-lab charges is greater than the $40 coinsurance on the $200 in non-lab charges. (For the PS&R, the A/B MAC (Part A) records $40 coinsurance and $60 primary payment.) EXAMPLE 2: Deductible Not Met Outpatient services were furnished to a Medicare beneficiary for whom the provider billed $100 for lab services and $200 for emergency room services. The lab fee schedule amount for the $100 lab services is $70. Only $158.00 of the beneficiary's Part B deductible had been met previously leaving the remaining $75.00 to be met. The primary payer paid $150 for Medicare covered services without designating what portion of its payment was for each type of service. Since the ratio of lab charges to non- lab charges is $100/$200, the A/B MAC (Part A) divides the primary payer's payment of $150 into two amounts based upon the same ratio: $100/$200 = $50/$100. It applies $50 of the primary payer's payment to the $70 lab fee schedule amount and the remaining $100 to the $200 in non-lab charges (emergency room services). It calculates the deductible and coinsurance in the usual manner based upon the $200 non-lab charges. It does not charge any deductible or coinsurance since the primary payment of $100 allocated to non-lab charges is equal to the $25 coinsurance and $75 remaining deductible on the $200 in non-lab charges. (For the PS&R, the A/B MAC (Part A) records $75 deductible and $25 coinsurance.)