Mattila appears regularly in the major opera houses worldwide, including the Metropolitan Opera, the Royal Opera House in London, Théâtre du Châtelet, Opéra Bastille, the Lyric Opera of Chicago, San Francisco Opera, Houston Grand Opera, Vienna State Opera, Toronto Roy Thomson Hall, and Großes Festspielhaus in Salzburg.
She was seen as Emma in the first ever televised production of Schubert's Fierrabras at the Vienna State Opera in 1988. In 1990 she made her Metropolitan Opera debut as Donna Elvira in Mozart's Don Giovanni. In 1994, she made her Spanish debut as Tatyana in Tchaikovsky's Eugene Onegin in Madrid, and 1996 debuts in Paris in Wagner's Lohengrin, Verdi's Don Carlos.
Mattila has won Grammy Awards for "Best Opera Recording" for Die Meistersinger von Nürnberg in 1998 and for Jenůfa in 2004. She was awarded the Evening Standard Ballet, Opera and Classical Music Award for “Outstanding Performance of the Year” in 1998 for her performance of Elisabeth in Don Carlos at the Royal Opera House. In 2001 The New York Times chose Karita Mattila as the best singer of the year for her performance in Fidelio at the Metropolitan Opera, and in the same year she was nominated for the Laurence Olivier Award “Outstanding Achievement in Opera”.
Mattila's 2004 New York performances in Salome and subsequent Káťa Kabanová inspired the New York press to write: "When the history of the Metropolitan Opera around the time of the millennium is written, Karita Mattila will deserve her own chapter."
In 2005, she was named Musician of the Year 2005 by Musical America, which describes her "the most electrifying singing actress of our day, the kind of performer who renews an aging art form and drives the public into frenzies." BBC Music Magazine named Mattila as one of the top 20 sopranos of the recorded era in 2007.
- Arias & Scenes (Erato) cond. Yutaka Sado; Queen of Spades, Jenufa, Elektra.
- German Romantic Arias (Erato), Staatskapelle Dresden, cond. Sir Colin Davis; Beethoven, Weber.
- Strauss: Orchestral Songs; Four Last Songs (DG)
- Strauss: Orchestral Songs (Sony Music Entertainment)
- Strauss: Hölderlin Lieder (Sony Music Entertainment)
- Sibelius Songs (Ondine)
- Grieg and Sibelius Songs (Erato)
- Lollipops; Canteloube, Villa-Lobos (Philips)
- Sydän Suomessa – From the Heart of Finland (Ondine), 1996, recital with Ilmo Ranta (piano); songs by Toivo Kuula, Oskar Merikanto, Erkki Melartin, Yrjö Kilpinen and folk songs.
- Wild Rose (Ondine) with Ilmo Ranta. Lieder by Beethoven, Brahms, Schubert, Schumann, Mahler.
- Modern Portrait (Warner/Finlandia), 1995. Paul Hindemith Das Marienleben, song cycle for soprano & piano, Op. 27; Aulis Sallinen Dream Songs; Mikko Heinio song cycle Vuelo de Alambre
- Karita Live! (Ondine) cond. Jukka Pekka Saraste; Wagner, Verdi, Strauss, Gershwin
- Helsinki Recital (Ondine), Martin Katz (piano); Duparc, Kaija Saariaho Quatre instants, Rachmaninov, Dvořák Gypsy songs.
- Excellence – The Artistry of Karita Mattila (Ondine)
- Salome (Sony Music Entertainment)
- Káťa Kabanová (Fra Musica)
- Tosca (Virgin)
- Manon Lescaut (EMI Classics)
- Don Carlos (EMI Classics)
- Fidelio (DG)
- Die Meistersinger (Decca, DG)
- Simon Boccanegra (TDK)
- Jenůfa (Erato)
- Le nozze di Figaro (Sony Music Entertainment)
- Così fan tutte (Philips)
- Don Giovanni (Philips)
- Fierrabras (DG)
- Der Freischütz (Decca)
- Scenes from Goethe's Faust (Sony Music Entertainment)
- Mozart: Requiem (DG)
- Beethoven: Symphony no. 9 (DG)
- Shostakovich: Symphony no. 14 (EMI Classics)
- Schoenberg: Gurrelieder (EMI Classics)
- Bernstein: Symphony no. 3 (Erato)
- Sibelius: Kullervo (BIS)
- Mendelssohn: Symphony no. 2 (DG)
- Schubert: Mass in E flat major; Mozart: Aria of the Angel, Laudate dominum (DG)
- Fever (Ondine)
- Best of Evergreens (Ondine)
- Karita's Christmas (Ondine)
- Songs To The Sea; Popular Melodies by Lasse Mårtenson (2001)
- "Are these the 20 best sopranos of the recorded era?". The Guardian. 2007. Retrieved 4 December 2016.
- Ondine 0 ODE892-2 (58 minutes: DDD). Texts and translations included. Recorded in association with Helsingin Energia. Gramophone review
- Ondine Records: Biography and discography
- Karita Mattila Forum
- Met Opera Review | "'Salome' Unveils Emotions (and a Soprano)," Anthony Tommasini, New York Times, March 17, 2004
- "Mysteries of Love: Karita Mattila's Salome," Alex Ross, The New Yorker, April 5, 2004
- Interview with Classical Voice
- Karita Mattila's career, roles, CDs and DVDs on Mostly Opera