Hanli Stapela's extensive career on the stage has taken her all over southern Africa, as well as Europe, the USA and Mauritius. She has won numerous awards for her operatic performances and while her repertoire includes a wide range of roles, she is also a consummate concert artist, regularly performing lieder, oratorio and other orchestral works. Her performances also included several official state functions and concerts at South African embassies worldwide and in Washington DC she performed at a concert for the Chinese ambassador to the USA.
Her career in the theatre started as opera repetiteur at the State Theatre Pretoria. It was this stint that convinced her to pursue a career as a singer. Soon she was contracted by the Pro Musica theatre to sing the composer in Ariadne auf Naxos, which launched her operatic career. She was offered a contract at the State Theatre where she rose to the position of principal soloist before embarking on a freelance career. Her roles include Lucia (Lucia di Lammermoor), Violetta (La Traviata), Gilda (Rigoletto), Olympia and Antonia (Les Contes d'Hoffmann), Norina (Don Pasquale), Donna Anna (Don Giovanni), Ilia (Idomeneo), Hanna Glawari (The Merry Widow), the Countess (Le nozze die Figaro), Pamina (Die Zauberflöte), Fiordiligi (Così fan tutte), Manon (Manon), Marguerite (Faust), Baby Doe (The ballad of Baby Doe), Mimi (La Bohème), Micaela, Nedda (I pagliacci) and Cio Cio San (Madama Butterfly). She became widely known to radio and television audiences through numerous concert and opera performances as well as a personal profile on Kyknet.
She lived in the USA for many years, where she performed widely with orchestras and as recitalist, appeared as Rosalinda (Die Fledermaus) at the Lincoln Center's Avery Fisher Hall and added several American compositions to her repertoire, like Baby Doe (The Ballad of Baby Doe) by Douglas Moore and Samuel Barber's Knoxville: Summer of 1915. A review of her portrayal of the protagonist in the opera The Ballad of Baby Doe stated:
"Soprano Hanli Stapela was superior to performances I've heard on recordings from (Beverly) Sills and Jan Grissom, or seen in Central City, New York, Bloomington (Indiana) with other Baby Does. The richness and brightness of Stapela's voice, the narrow vibrato and wonderful phrasing, her ability to soar into the high tessitura with complete ease…"
Since her return to South Africa she has been teaching voice and is currently associated with Tshwane University of Technology and University of Pretoria as well as maintaining a private studio.