Judith Howarth studied first with Marilyn Smith and then with Patricia MacMahon at RSAMD, now the Royal Conservatoire of Scotland. On leaving RSAMD she was immediately engaged as a principal soprano at the Royal Opera House Covent Garden and during 9 seasons sang many roles including Woglinde (Das Rheingold and Götterdämmerung), Gianetta (L'Elisir d'Amore), Susanna (Figaro), Elivira (L'Italiana in Algeri), Norina (Don Pasquale), Morgana (Alcina), Frasquita (Carmen), Siebel (Faust), Cressida (Troilus and Cressida), Marguerite de Valois (Les Huguenots), Adele (Die Fledermaus), Marzelline (Fidelio), Musetta (La Bohème), Liu (Turandot), Gilda (Rigoletto) and many more.

Since leaving the Royal Opera, Judith has sung with some of the best opera houses all over the world and with some of the best coaches and conductors including Abbado, Sinopoli, Haitink, Solti, Pappano, Mackerras, Mehta, Davis, Barenboim and many more. Her roles have been wide ranging, with performances in Figaro, Ballo in Maschera, Tales of Hoffmann, La Traviata, Parsifal, Fidelio, Turandot, Il Turco in Italia, Peter Grimes, Rigoletto, Pearl Fishers, Nixon in China, and the acclaimed Madam Butterfly produced by Anthony Minghella at English National Opera, Minnesota Opera, Welsh National Opera and Finnish National Opera. Most recently she has had huge success with Maria Stuarda in Minnesota and with Welsh National opera in Britain and Oman. Guillaume Tell at the Rossini festival in Bad Wildbad which was recorded and will be released soon and a new production of Don Carlos in Finnish National Opera.

Judith has appeared all over the world in concert including Mozart Mass in C minor at the Edinburgh festival with John Elliot Gardner, Der Shauspieldirektor at the Salzburg Festival with Frans Bruggen, Strauss Four Last Songs many times including in Vienna with Sir Simon Rattle, Elijah with George Pretre in Vienna. She has toured in concert with Placido Domingo in Amsterdam (live TV), Brussels, London, Adelaide, Auckland and Hong Kong.

Judith has made numerous recordings including Spirit of England (Elgar) and Walton's Troilus and Cressida which won the Gramophone opera recording of the year award. She has also appeared many times on the television, radio and video.