Harteros was born in Bergneustadt, North Rhine-Westphalia, to a Greek father and a German mother and has two siblings, Alexia and Georgios. As a child, she was encouraged by her parents to pursue classical music and singing. Eventually, her music teacher at the Wüllenweber-Gymnasium in Bergneustadt, August Wilhelm Welp, noticed her considerable talent and recommended that she be professionally educated in singing. At the age of 14 (in 1986), she started voice training under Astrid Huber-Aulmann in Gummersbach, concurrently with her schooling.
Her first performances were in music institute concerts and in a school production of The Marriage of Figaro in 1990, as the Countess. In 1992 she gave her first concert at the Kantonsschule Schwyz in Switzerland.
From 1990, her musical education was entrusted to the technically experienced conductor and repetiteur Wolfgang Kastorp at the Cologne Opera, who accompanied her in a series of concerts.
After completing high school in 1991, Harteros continued her voice studies under Liselotte Hammes at the Cologne University of Music. Her original singing teacher, Huber-Aulmann, continued to teach her until early 1996, and Harteros accompanied Huber-Aulmann on concerts tours in 1993 and 1994 to Russia and the United States, which attracted lots of attention to the singer.
Just before her final exams, she was employed as a permanent member of the ensemble at the Schillertheater in Gelsenkirchen and Wuppertal. After her 1996 exams, she was given a permanent position with the ensemble at the opera in Bonn.
In the summer of 1999, she won the BBC Cardiff Singer of the World competition, which led to many invitations for concerts and guest performances. This was the major breakthrough for her career: since then, she has appeared as a guest at all the major world opera houses, including Frankfurt, Lyon, Amsterdam, Dresden, Paris, Hamburg, Vienna, New York (Metropolitan Opera), Munich, Cologne, and Berlin (Deutsche Oper), as well as the Salzburger Festspiele. She has also given concerts and Lieder recitals all over Germany, as well as in Boston, Florence, London, Edinburgh, Vicenza and Tel Aviv. She sang the title role in a new production of Händel's Alcina at the opera festival in Munich in 2005.
Her repertoire includes the roles of Mimì (La bohème), Desdemona (Otello), Micaëla (Carmen), Eva (Die Meistersinger von Nürnberg), Elisabeth (Tannhäuser), Fiordiligi (Così fan tutte), Contessa (Le nozze di Figaro), Arabella (Arabella), Alice Ford (Falstaff), and Alcina.
- List of reviews and articles in Opera News including, Martin Bernheimer, 'Donna Anja' (cover story) Opera News, March 2004.
- Anne Midgette, 'The (New) Women of Figaro', New York Times, September 28, 2003