CMS Pub. 100-04, ch. 21, § 10

Effective July 1, 2002, the MSN is used by all A/B MACs (A), (B), (HHH), and DME

MACs.

The MSN is the primary vehicle by which beneficiaries are notified of decisions on their

claims for Medicare benefits. The A/B MAC (A), (B), (HHH), or DME MAC mails a

single MSN at the end of the month to each beneficiary for whom claim was processed

during the month to inform the beneficiary of the disposition of all claims. All MACs

shall issue No-Pay MSNs on a 180-day mailing cycle. MSNs with checks to the

beneficiary will continue to be mailed out as processed. To ensure that all messages are

uniform throughout the Medicare program, A/B MACs (A), (B), (HHH), and DME

MACs may not use locally developed MSN messages until approved by the regional

office (RO).

The MSNs are not sent to providers. Providers receive remittance advice records. (See

Chapter 22 for instructions about the provider remittance record.)

The MSN contains the following sections or areas:

• Disclaimer;

• Title;

• Claims Information;

• Message; and

• Appeals.

Detailed requirements for completion of each section are included in §10.3. Generally,

A/B MAC (A), (B), (HHH), or DME MAC requirements are the same. Where there are

differences or where the specific specification applies to only the A/B MAC (B)/DME

MAC or to only the A/B MAC (A)/(HHH), the difference is noted in the specific

instruction.

Although every attempt has been made to make the MSN as simple as possible, the

MSN is sufficiently complex that MACs must maintain continuing training efforts

directed at beneficiaries and providers for understanding and interpretation of data on the

MSN. Although providers are not mailed copies of MSNs, beneficiaries frequently

show MSNs to providers to establish deductible status for provider billing.