Her mother was a flute player, while her sister played clarinet and sang, and her father was an ongoing music encyclopedia.

Meanwhile, she continued studying between 2005 and 2010 at the Drachtster Lyceum obtaining her high school diploma and following with a Communications Bachelor.

Iris Kroes' entry of The Voice of Holland started from her Blind Audition at September 30, 2011 where she sang Someone Like You by Adele accompanied herself on harp.

Many of her renditions during the show became chart entries in the Dutch Single Top 100, like "Foolish Games" (#76), "Listen to Your Heart" (#83), "When Love Takes Over" (#100).

[7] Kroes was also on tour with her former coach Marco Borsato, which she performed at the Ziggo Dome include twice in 2012.

On 15 January 2014, Kroes' new single Never Coming Back was released with supported by its Theatre Program Thús, with her vocals and harp and a string ensemble from the North Pole Orchestra.

[11] On 23 July 2014 Kroes played and sang the song I still cry, originally written by Julie Miller and performed by Ilse de Lange, during the national memorial service Verbonden in Verdriet (Connected in Sorrow) in the Sint Joriskerk in Amersfoort for Malaysia Airlines Flight 17 Air Disaster with her performance reported worldwide through CNN.

On June 27, 2015, Iris released her first song in Dutch language, Bijna Met Jou (English: Almost With You) for the project 'Fietsliedjes' from provence Drenthe for showing why they are the number one bicycle province of the Netherlands.