Medicare Payment Rate Disclosure Act of 2012 - Amends title XVIII (Medicare) of the Social Security Act to direct the Secretary of Health and Human Services (HHS) to make publicly available on the official Medicare Internet site during a specified initial period: (1) Medicare payment rates for frequently reimbursed hospital inpatient and outpatient procedures and services, as well as for physicians' services; and (2) the period for which payment rates are applicable. Requires posting also after the initial period of an expanded selection of such items.
Directs the Secretary to select at least 30 procedures and services for the basic posting and at least 100 procedures and services for the expanded posting.