Cellia Costea made her professional debut in 1999 on the stage of the Bucharest National Opera, Romania, in the role of Desdemona in Otello by G. Verdi, and the international career having as starting point the role of the Countess of Le Nozze di Figaro by W. A. Mozart, in 2001 on stage of Klagenfurt Stadttheater, Austria.
She is the winner of 11 international singing competitions, the most important being:
1st Prize at the XX Concorso Internazionale Valsesia Musica 2004
1st Prize and the Public Prize at the XL International Competition “Francisco Vinas”, Barcelona 2003
1st Prize and the Public Prize at The 2nd International Singers Competition Beijing, China 2002
1st Prize and the Public Prize at Debut Bad Mergentheim, Germany 2002
2nd Prize at “Jaime Aragall” Girona, Spain 2002
1st Prize and the Public Prize at “Montserrat Caballe” Andora 2001
1st Prize at “Jullian Gayarre” Pamplona, Spain 2000. President of Jury: Jose Carreras

This led to many engagements worldwide: London Covent Garden, Wiener Staatsoper, Liceu de Barcelona, Deutsche Oper Berlin, Berlin Konzerthaus, Frankfurt Theater, Stuttgart Staatstheater, Klagenfurt Staatstheater, Hannover Staatstheater, Oslo Oper Theater, Opera West Bergen, Opèra Municipal de Marseille, Opera Royal de Wallonie de Liege, Orchestra Sinfonica Siciliana di Palermo, Teatro Massimo Bellini di Catania, National Theater Prague, Bucharest National Opera, Timisoara Opera House, Teatro Municipale Santiago de Chile, Opera de Nice, Cairo Opera House, Greek Opera House, Herodes Atticus Theater of Athens, Megaro Moussikis of Athens, Beijing National Opera, Teatro Municipal de Santiago de Chile, Circuito Lombardo: Brescia, Cremona, Pavia, Como, Reggio Emilia, Teatro Luciano Pavarotti Modena, Teatro Comunale Piacenza, Teatro Politeama Greco Lecce, Teatro Coccia Novara, Teatro Lirico Cagliari, Nuovo Teatro Verdi Sassari, Opera de Toulon, Bavarian Opera House, De Nederlandse Opera, Theatre du Capitol Toulouse, Deutsche Oper am Rhein, Amsterdam Concertgebouw, Royal Opera Amsterdam, Seoul Art Center. Some of the most important protagonist roles are Contessa in Le nozze di Figaro, Arminda in La finta giardiniera, Donna Elvira in Don Giovanni, Michaela in Carmen, Marguerite in Faust, Liu in Turandot, Mimi in La Boheme, Tosca, Madama Butterfly, Nedda in Pagliacci, Aida, Amelia in Simon Boccanegra, Leonora in Trovatore, Desdemona in Otello, Elena in I Vespri Siciliani, Amelia in Ballo in Maschera, Elisabetta in Don Carlo, Maddalena in Andrea Chenier, Santuzza in Cavaleria Rusticana, Margherita and Elena in Mefistofele. 

The important directors with whom he collaborates are Seiji Osawa, Juliano Carella, Mark Elder, Ascher Fisch, Eugene Kohn, Jiri Kout, Alain Lombard, Pinchas Steinberg, Alberto Veronesi, Abel Ybes, Gianpaolo Bisanti, Andrea Batistoni, Omer Meir Wellber, Phillipe Auguin.

Mrs Costea’s past season 2017 includes Aida at Arena di Verona in Italy, Teatro Municipale Santiago de Chile in Chile, and Tibilisi Opera House in Georgia, Floria Tosca in Tosca at Staatstheater Stuttgart and Deutsche Oper am Rhein Dussedorf in Germany, Amelia in Ballo in Maschera at Bavarian Opera House in Munich, Opera Gala at St.Petersburg in Russia, and Floria Tosca in Tosca and Cio Cio San in Madama Butterfly at Herodes Atticus Theater of Athens, Greece.

The 2018 season included Floria Tosca in Tosca at Staatstheater Stuttgart, Germany, and Greek National Opera House in Athens, Greece, Elisabetta in Don Carlo at Bucharest Opera House in Romania, Elena in Mefistofele at Bavarian Opera House, and Santuzza in Cavaleria Rusticana at Deutsche Oper am Rhein Dussedorf in Germany.
The 2019 season included Floria Tosca in Tosca at Staatstheater Stuttgart, Amelia in Simon Boccanegra at Greek National Opera House in Athens, Greece, Cio Cio San in Madama Butterfly at Teatro Petruzzelli of Bari, Italy, Elena in Mefistofele at National Opera of Craiova, Adalgisa in Norma at Herodes Atticus Theater of Athens, Greece, Maddalena in Andrea Chenier at Opera de Toulon and Opera de Nice, France, Elisabetta in Don Carlo at Greek National Opera House in Athens, Greece.

The 2021 season included two concerts Opera Gala together with the famous star mezzo-soprano Elina Garanca and conductor Karel Mark Chichon in Austria, The 7 Deaths of Maria Callas, Marina’s Abramovic Production (Casta Diva – Norma) as well as Floria Tosca in Tosca at the National Opera Iasi, Romania.

The 2022 season included Maddalena in Andrea Chenier and Desdemona in Otello at Greek National Opera House and new projects are coming: Elisabetta in Don Carlo at Bucharest Opera House, Aida at Timisoara Opera House ,Amelia in Un ballo in maschera at Iasi Opera House ,Margherita in Mefistofele at Bucharest Opera House.

Cellia Costea was born in 1975 into a family of musicians. She studied violin at the Music School in Piatra Neamț and later singing, with Elena Botez at the Art High School in the same city. She continued her studies at the University of Music in Bucharest. Since 2012 she is the soloist of the National Opera in Athens, Greece, the year in which she receives from the Union of Greek Theater and Music Critics, the Grand Prize for the best artist of the year.