[3] He is now a frequent guest of the Opernhaus Zürich, the Royal Opera House in London, the Staatsoper Berlin, Deutsche Oper, the Semperoper Dresden, the Wiener Staatsoper, the Opéra national de Paris, the Théâtre des Champs-Élysées, Opera national de Bordeaux, Teatro alla Scala in Milan, and the Salzburg Whitsun Festival and Salzburg Festival.

Bernheim joined the Opernhaus Zürich troupe in 2010, where he was engaged to perform in myriad productions, including: Emmanuele in the world premiere of Marc-André Dalbavie's Gesualdo, directed by Patrice Caurier et Moshe Leiser.

[4] Between 2012 and 2015 he added multiple roles to his repertoire, most notedly: Cassio (Otello), Narraboth (Salome), Tebaldo (I Capuleti e I Montechi), Matteo (Arabella), Tamino (Die Zauberflöte), Spakos (Cléopatre), and Eginhard (Fierrabras).

[5] The 2015/16 season marked a turning point in his career, as he began making his debut in leading tenor roles at opera houses throughout Europe and the United States.

He performed as Rodolfo (La bohème) at Opernhaus Zürich,[6] Erik (Der Fliegende Holländer)[7] and Matteo (Arabella) at Semperoper Dresden,[8] Cassio (Otello) at Salzburg Osterfestspiele,[9] Tebaldo (I Capuleti e i Montecchi) at Opernhaus Zurich,[10] Italian Singer (Der Rosenkavalier) at Teatro alla Scala,[11] and as Roméo in Gounod's Roméo et Juliette at Dutch National Opera.

[22] In the 2017/18 season, Bernheim championed the role of Rodolfo in La bohème, performing it in two productions at Royal Opera House London[23] and once at Opéra national de Paris.

[24] He performed as Alfredo (La traviata) at Staatsoper Berlin[25] and Opernhaus Zürich,[26] and as the title role of Faust at Lyric Opera of Chicago[27] and Théâtre des Champs-Elysées.

[40] In concert Bernheim performed Puccini's Messa di Gloria with the London Symphony Orchestra conducted by Sir Antonio Pappano[41] and at the Wiener Staatsoper celebration commemorating 150 Years Vienna State Opera[42] being on the Ring.

[69] To begin the 2023/24 season, Bernheim performed the role of Ruggero Lastouc in the new Christof Loy production of Puccini’s opera, La rondine, opposite Ermonela Jaho at the Opernhaus Zürich.

[73] He signed an exclusive contract with Deutsche Grammophon in 2018, and his debut album, recorded with the PKF - Prague Philharmonia, conducted by Emmanuel Villaume was released on November 8, 2019.