Higher income individuals will be subject to an additional 0.9 percent Medicare tax effective January 1, 2013.  The additional Medicare tax will affect  single filers with wages in excess of $200,000, married couples filing a joint return with wages in excess of $250,000 and wages in excess of $125,000 for married filing separately.  This means that the portion of wages in excess of these amounts will be subject to a 2.35 percent Medicare tax.

The additional Medicare tax also affects self employed individuals.

This tax is imposed on the combined wages of those filing married filing jointly.  Thus these taxpayers may want to determine if filing separate returns will result in a lower tax liability.