Individuals and families who are looking at buying health insurance on the newly opened insurance exchanges may qualify for a tax credit that subsidizes the premium cost. To qualify for the credit you must have household income between 100% and 400% of the federal poverty level. For individuals that means income between $11,490 and $45,960. For a family of four, income must be between $23,550 and $94,200. In addition to the income requirements, individuals who are eligible for Medicare, other federal insurance or a qualified plan at work do not get the credit.