2018 - Additional Medicare tax
Answer:
There is an 0.9% additional Medicare tax on wages and self-employment income exceeding $250,000 if married filing jointly; $200,000, if single, head of household, or a qualifying widow/widower; or $125,000, if married filing separately.
To the extent the tax was not withheld from your wages, you will have to pay it when you file Form 1040
To the extent the tax was not withheld from your wages, you will have to pay it when you file Form 1040