"Beginning in 2014, ACA requires most individuals to maintain health insurance coverage or otherwise pay a penalty. Specifically, most individuals will be required to maintain minimum essential coverage, which is a term defined in ACA and its implementing regulations and includes most private and public coverage (e.g., employer-sponsored coverage, individual coverage, Medicare, and Medicaid, among others). Some individuals will be exempt from the mandate and the penalty, while others may receive financial assistance to help them pay for the cost of health insurance coverage and the costs associated with using health care services. [...] Individuals who do not maintain minimum essential coverage and are not exempt from the mandate will have to pay a penalty for each month of noncompliance with the mandate. The penalty is the greater of a flat dollar amount or a percentage of applicable income. In 2014, the annual penalty is the greater of $95 or 1% of applicable income; the penalty increases in 2015 and 2016 and is adjusted for inflation thereafter."
CRS Report for Congress, R41331