The network, which already hosts DC Comics hits The Flash, iZombie, Arrow, and DC's Legends of Tomorrow, will see the Girl of Steel join its already-overflowing lineup next fall.
Earlier this year, The CW renewed all 11 of its ongoing series. Containment, currently being billed as a miniseries event, was originally speculated as a contender for a slot on next year's schedule, but with Supergirl being added to the schedule that might be a hard thing to manage.
Les Moonves, the head of CBS, had previously said that the network planned to renew all of its freshman series, including Supergirl, but recent reports have suggested that the network has been sparring with Warner Bros. over licensing fees.
Supergirl had the biggest debut of the 2015-2016 season, but lost about half of its viewers over the course of its first season. While it remained one of CBS's biggest shows, the cost of making the series is significant. Even before licensing fees, it's reported that Supergirl costs about $3 million per episode.
Rumors have indicated that the show will head to Vancouver, where tax incentives will reduce the cost of production. In its first season, Supergirl filmed in Los Angeles. It's not yet clear whether any members of the cast might not make the trek to Canada to film, or what time slot The CW will place Supergirl in. The CW would not confirm for EW whether the reported move to Vancouver will actually happen.
One of the highest-rated and most buzzed-about episodes of Supergirl this year was its crossover with The Flash. A move to The CW -- especially if the movie is also physical and production is relocated to Vancouver -- likely would mean an increase in crossover opportunities with the DC Universe set up at the network. Supergirl shares executive producers Greg Berlanti and Andrew Kreisberg with Arrow, The Flash, and DC's Legends of Tomorrow.