Cristin Milioti first appeared in the Episode: "Bad Boys" of the American medical drama television series ‘3 lbs’ in 2006. That same year, she also became a part of the American crime drama television series ‘The Sopranos.’ She played the role of ‘Catherine Sacrimoni’ and appeared in 3 episodes of the show. She made her big-screen debut in the 2007 American coming-of-age romantic comedy film ‘Greetings from the Shore’ directed by Greg Chwerchak. The film received a mixed response from critics. In 2009, she starred as ‘Sammy Smalls’ in the Canadian romantic comedy film ‘Year of the Carnivore’ directed by Sook-Yin Lee. The film opened to mixed reviews from critics. She played the role of ‘Janet Pandamiglio’ in the 2012 American independent comedy film ‘Sleepwalk with Me’ directed by Mike Birbiglia. The film received mostly positive reviews.
In 2013, she joined the cast of the American sitcom ‘How I Met Your Mother.’ She played the role of ‘Tracy McConnell / The Mother’ and remained a part of the series until it went off-air in 2014. She next starred as ‘Zelda Vasco’ in the American romantic comedy television series ‘A to Z’ in 2014. The series aired its final episode in 2015. Milioti next appeared in television series like ‘Fargo’ (2015), ‘The Mindy Project’ (2015-2016), ‘The Venture Bros.’ (2016-2018), ‘Black Mirror’ (2017), ‘No Activity’ (2018), ‘Modern Love’ (2019), ‘Mythic Quest: Raven's Banquet’ (2020), and ‘Death to 2020’ (2020). She starred as ‘Sarah Wilder’ in the 2020 American science fiction romantic comedy film ‘Palm Springs’ directed by Max Barbakow. The film was met with critical acclaim with critics praising the performance of the cast. Milioti also received the Critics' Choice Super Award for her performance in the film.
In 2021 she grabbed the role of ‘Hazel Green’ in the American dark comedy television series ‘Made for Love.’ The series was renewed for a second season in June 2021. That same year, she also made an appearance in television series like ‘Ziwe,’ ‘The Simpsons,’ and ‘Death to 2021.’