After Rossum broke the news on her Facebook page, executive producer and showrunner John Wells promised “a Gallagher-worthy sendoff for Fiona that honors the great work Emmy has done.”
Wells said the cast and crew are currently working on the Season 9 finale.
The first half of Season 9 premieres in September, with the finale set to air in March 2019.
“It is always bittersweet when an ensemble member decides to move out of the proverbial house, but our door will always remain open for Fiona to return home for a visit, or to move back in,” Wells wrote. “I look forward to continuing the stories of this wildly unpredictable family and all of us on ‘Shameless’ will miss Emmy and her wonderful Fiona.”
According to Warner Bros., which produces the series, Rossum is leaving to explore “the next chapter in her career.”
Rossum’s time on “Shameless,” while critically hailed, never materialized any awards recognition for the actress.
The show afforded Rossum a chance to step into the role of director for the first time.
“I am a great believer in: You should know what you don’t know,” she told CNN last year. “I still don’t know a lot, but this is just the beginning of me figuring out what I don’t know, I guess.”
It is not known whether “Shameless” will have a Season 10. It was officially picked up for Season 9 in November of last year.
Rossum, however, seemed positive about the possibility of the show’s future after her departure.
“I know you will continue on without me, for now. There is much more Gallagher story to be told,” she wrote on Facebook. “I will always be rooting for my family. Try not to think of me as gone, just think of me as moving down the block.”