[3][4] He later joined Gloria Bistrița, making his first division debut under coach Ioan Sabău in a 1–0 away victory over Unirea Urziceni on 23 May 2007.

[6][7] He spent the following season on loan at Gloria Bistrița, as the Roș-albaștrii already had a first-choice goalkeeper in the person of Róbinson Zapata.

Tătărușanu made his European debut on 16 July 2009, in a 2–0 victory against Hungarian side Újpest in the UEFA Europa League.

On 19 August 2010, he helped his team progress further to the Europa League group stage after making two saves at the penalty shootout against Grasshopper.

Tătărușanu refused to renew his contract with Steaua București and left the club on Bosman ruling, subsequently signing a five-year deal with Italian team Fiorentina on 9 June 2014.

Following the departure of Neto to Juventus in July 2015, Tătărușanu became the undisputed first-choice goalkeeper for Fiorentina, with his good display earning him the Gazeta Sporturilor's 2015 Romanian Footballer of the Year award.

He only played six matches overall during his one-year spell at Lyon, as he was considered a backup option to regular starter Anthony Lopes.

[22] Tătărușanu played in a Derby della Madonnina in the Coppa Italia in January 2021, being praised for his performance in the media despite his team being defeated 2–1 by Inter Milan.

With Tătărușanu in goal, Milan went on a four-game winning streak in the Serie A against Hellas Verona, Bologna, Torino and Roma.