Use of Modified Adjusted Gross Income (MAGI) in Federal Health Programs [February 25, 2016] [open pdf - 728KB]
"The Patient Protection and Affordable Care Act (ACA; P.L. 111-148, as amended) created Section 36(B) of the Internal Revenue Code (IRC) to define household income, based on modified adjusted gross income (MAGI). MAGI is used to determine (1) penalty amounts owed if a person does not comply with the individual mandate or whether an individual is exempt from the individual mandate; (2) eligibility for and the amount of a premium credit to purchase coverage through a health insurance exchange; and (3) Medicaid income eligibility for certain populations. MAGI is also used to determine which Medicare beneficiaries pay high-income premiums. However, MAGI has many different definitions, depending on the purpose for which it is being calculated. For these government health programs, MAGI begins with adjusted gross income (AGI) as calculated for tax purposes. From there, various types of income are included (or, in the case of Medicaid, subtracted) to calculate MAGI for each particular program. Although the different health programs use the word 'household,' they do not necessarily refer to the same groupings of people. For example, married couples living together are counted as the same Medicaid household regardless of whether they file a joint tax return. By contrast, married couples must file a joint tax return to be eligible for premium credits. This report explores the different MAGI definitions across health programs, including Medicare, the health insurance exchanges under the ACA, and Medicaid. It also addresses why MAGI is used, and how it is applied, specific to each program."
CRS Report for Congress, R43861
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html