Turati originally joined Sassuolo in 2018 after coming through the Inter academy, although his route to establishing himself at the club has included loan spells elsewhere in Italy.
The goalkeeper spent time with Reggina, Frosinone and Monza before returning to Sassuolo last season as the deputy to Muric.
His new agreement keeps him at the club until June 2031 and represents a long-term commitment to a goalkeeper who has spent much of his career developing away from Sassuolo.
Turati has not yet made a league appearance this season, but he has featured once in the Coppa Italia.
His opportunity came in the last-32 tie against Frosinone, when he started and helped Sassuolo progress after a penalty shootout.
The club announced the renewal with a message wishing Turati well for the continuation of his career in black and green.
For Turati, the new contract provides further security after several seasons spent moving between clubs in search of regular first-team football.
His spell at Frosinone was particularly important in that development, while his subsequent time at Monza gave him further experience before returning to Sassuolo.
Now the club has committed to keeping him in its plans for the long term.
At 25, Turati still has considerable room to develop, and Sassuolo's decision to extend his contract until 2031 underlines the belief that he can remain an important part of the squad over the coming years.