Which Seinfeld characters are Jewish?

Apart from Jerry and both his parents of course, a better question is who isn't, answer Kramer.

George, both his parents, Elaine and Newman all are, though as NBC didn't want it to have a minority appeal, none are given their genuine religion in the programme except Jerry and his family.

While most of the actors in the show were in fact Jewish, the only characters who were Jewish were the members of the Seinfeld family, Mr. Lipman of Pendant Publishing, and the rabbi from Elaine's building.

Don't forget Dr Wattley the Dentist! He changed religion to Judaism just for the jokes.

As I said, few beyond the actual Seinfeld family are supposed to be Jewish in the show (even though they behave as if they are) but the actors are, and it's quite amusing for anyone Jewish to see someone like Elaine playing a shiksa. Normally it's the other way round, with non-Jews being cast as Jews and either desperately overacting or looking and acting exactly like shiksas and goyim!