Antipático
The opposite of simpatico would be antipático.
Malo
How nice of you. NOTE the word simpatico is misused in this sentence. Simpatico means nice in spanish, but it is not used as a verb. Some one can be nice. But the act of DOING something nice would use a different word. And by the same token the word simpatico is only used when referring to a person's personality being nice. It is to refer to food or weather or any inanimate thing as nice. I can be used for animals, but it is really not a proper use. Simpatico is a specific word that means a specific thing of a person being nice.
The English word for "simpático" is "friendly" or "pleasant."
simpatico/simpatica-sympatheticbueno/buena-goodagradable
The word simpatico, meaning nice, pleasing, popular, cute, amusing funny has the antonym of antipatico. Antipatico means unpleasant, odious, unsympathetic, harsh or crabby.
Kind, as in 'you are kind' is simpatico, Kind as in 'what kind of dog is that?' is tipo
'simpatico' means nice/kind.
Simpatico - 2014 was released on: USA: 2014 (DVD premiere)
Simpatico - D-A-D album - was created in 1997.
Que simpatico - How nice! (What a nice person!) - Besitos - Little kisses.
simpatico/a