When does Supergirl return? At the risk of sounding corny, and that's a risk I'm always willing to take, the show will be back faster than a speeding bullet! According to TVLine's January return date calendar, Supergirl will return Monday, Jan. 4 to CBS. That's not long at all! While some shows take an extended hiatus at midseason, we're only going to be without Kara and her compatriots for a few weeks. Three, to be exact.