In addition to the Social Security considerations above, if Medicare wages (box 5) on your W-2, either before or after the correction, are more than $200,000, you must file an amended return because the change in Medicare wages will change the Additional Medicare Tax on Form 8959, or Form 8959 will be added to your tax return. If the total Medicare wages on all of your W-2s, plus net self-employment income, is more than $200,000, you also must file an amended return, because the change in Medicare wages will change or add Form 8959.
