Medicare Secondary Payer Manual (Pub. 100-05), Ch. 5 § 40.7.1
Crediting the Part B Deductible
40.7.1 - Crediting the Part B Deductible
(Rev. 11550; Issued: 08-12-22; Effective: 10-13-22; Implementation:10-13-22)
Expenses paid by the GHP count toward the Medicare deductible. For claims where
reasonable charge applies, the A/B MAC (Part B) and DME MAC credits the payment
made under the insurer's plan toward the Medicare deductible up to the amount of the
Medicare reasonable charge or fee amount for the service; i.e., if the primary plan paid
$75 on a procedure and the reasonable charge or fee amount for the procedure is $50,
the A/B MAC (Part B) and DME MAC credits $50 toward the deductible.
The A/B MAC (Part B) and DME MAC processes all claims to CWF, including those to
be denied because the claim has not been submitted to the primary payer, if the Medicare
deductible is unmet. If the beneficiary has GHP, and it is not reflected in the CWF
response, the A/B MAC (Part B) either updates the MSP auxiliary file with an "I"
indicator if it is sure of the MSP involvement (see §10.1 subsection 2), or if further
development is required, advises the MSP Contractor via ECRS, and pends the claim
awaiting the MSP Contractor results via CWF (See §10.2.1, above). DME MACs do not
create “I” records. In these situations, the DME MAC submits an ECRS Inquiry to the
MSP Contractor.