Sigridur Osk attended  the Royal College of Music  Opera School as a postgraduate student and  graduated  with an Artist Diploma and a Masters degree with merit.  Her singing teacher was Russell Smythe. Previously, she  had achieved a grade 8 in singing and a piano teaching diploma from the Reykjavík College of Music. Her current teacher is Sigrry Ella Magnus.

Sigridur Osk appears  frequently  in operas and has performed over 20 roles. She also appears in oratorios and as a recitalist in Iceland and abroad.  She recently sang the role of Rosina in Il Barbiere di Siviglia at the Icelandic Opera and Waltraute in Wagner´s „Ride of the Valkyries“  with Lidal North at the Norwegian Opera House.  She sang in the English National Opera‘s staging of  Jakob Lenz by Wolfgang Rihm and at Glyndebourne, she performed the role of Fifth Nun in the first performance of  Love and  Other Demons  by Peter Oötvös, conducted  Vladimir  Yorvosky.

Sigridur Osk has always been fascinated by music and theater, from a young age and through her teenage years training in dance at the National Theatre Ballet School in Iceland, studying piano and singing, and taking part in such plays and musicals as The Sound of Music and Cats at venues including the National Theatre of Iceland and and performing jazz standards. This somehow led her into the opera world and she finds this background really useful.

Sigridur recently had the opportunity to work with one of the leading contemporary dance companies in Sweden the Cullberg Ballet and recorded the vocals for the soundtrack of their coming up show called Plateau Effect by Jefta Van Dinther.

She appeared in „Insanity“ with the progressive Kiez Oper company  in Berlin and has frequently appeared in London with The Classical Opera Company, including the role of Arbate in Mitridate which earned her high praise in a review in The Times newspaper.  She performed Haydn‘s cantata Arianna a Naxos for them with the fortepianist Gary Cooper in Kings Place, London and sang on their behalf in In Tune in a live broadcast on BBC Radio 3.

With English Touring Opera she  sang the role of Arkane in the opera Teseo by Handel. Sigríður has appeared in many of the best known concert venues  in London, such as the Royal Albert Hall and St. Martin- in- the –Fields. In the Cadogan Hall  she sang a concert with Dame Emma Kirkby which was broadcast on Classic FM. Sigríður sang in a recording of Engel Lund´s Book of Folk Songs with the Lieder Theater London, published by Nimbus Records.

In Iceland´s  modern music festival  „ Dark Music Days“, she sang the first performance of the Adriana Songs by Kaia Saariaho and with the Electra Ensemble performed Chansons Madécasses by Ravel, which was chosen as one of the five best performances in 2011 by the radio arts programme, „Víðsjá“. Sigridur sang the role of the Queen of Shepa and Second Lady in Handels Solomon in august 2015 at the Festival of sacret arts in Hallgrímskirkja in Reykjavík with The Hage International Baroque Orchestra and conductor Hörður Áskelsson, the concert will be broadcasted worldwide.