Stamell first learned to dance at the age of 3 in Sydney, where she learned ballet, contemporary dance and tap. She says it took her until the age of 8 to find a Teacher who treated her properly, as a Dancer, rather than as someone with dwarfism. In 1994, she won the South Pacific Silver Star Tap Dancing Championships and in 2000 tap danced at the opening of the Sydney Olympics with the Tap Dogs. While studying dance, theatre and film at the University of New South Wales, Stamell developed a passion for theatre and acting. She acted in a number of short plays at the University, including Here's to the Small Minded, written by Matt Noffs and Caroline Camino. In the summer holiday of her first year, she got her first major role when she submitted herself for extra work in the film Moulin Rouge!. Her initial casting as an extra led to the part of La Petite Princess being created especially for her. The money earnt from the role allowed her to come to England and study Shakespearean and Jacobean plays. Following this, she performed with some of Australia's leading theatre companies, including her role as King Duncan in Macbeth for the Sydney Theatre Company and Cordelia in King Lear for Round Earth. She has also appeared in the Australian short film Love Hurts as Cupid. She has worked with some the world's leading dance innovators, Caroline Bowditch, Marc Brew, Sue Healey, John 'cha cha' O'Connell, Shaun Parker and Christina Tingskog.

In 2005, Stamell received funding from the Australia Council which brought her to England, where she studied Shakespearean and Jacobean plays at LAMDA. While this was initially intended to be a short summer in England, Stamell obtained a number of professional stage roles in the UK, performing with the Quarantine Theatre Company and Graeae Theatre Company and she renewed her interest in dance with a secondment to CandoCo. She was generally well reviewed for her work in Graeae Theatre Company's production of Whiter Than Snow playing a young Actress who wanted to break with stereotype and play the role of Snow White. Although otherwise filing a mixed review, Lyn Gardner of The Guardian wrote: "...the show raises interesting questions about humans' constant attempts to improve on nature, and as the diminutive heroine, Frieda, who longs to be Snow White but is always cast as a dwarf, Kiruna Stamell is outstanding." Stamell also toured extensively throughout Europe with Campo (formerly known as Victoria), with their production of For All The Wrong Reasons.

Stamell debuted on British television in 2009 when she appeared as Phoebe Tunstall in the six-part BBC drama series All the Small Things, and has made appearances on EastEnders as Sandra Fielding, starred in Cast Offs for Channel 4, and most recently as Amy in Life's Too Short for BBC 2. In 2012 Kiruna auditioned for series 4 of the Sky 1 series Got to Dance. She was unanimously voted through the first round, but got no further. She also appeared in Giuseppe Tornatore's film, The Best Offer appearing alongside Geoffrey Rush. As of 2014, Stamell is appearing in Great Britain at The National Theatre.

Stamell remains based in England. She is a frequent guest presenter on the BBC's Ouch! podcast. She has long been involved in the disability arts movement and was an original co-founder of Atypical Theatre Company in Australia. She is co-director of A Little Commitment Ltd, a production company run in conjunction with husband Gareth Berliner. The pair also produce a children's theatre show – Pirate and Parrot – and work with schools around disability issues.

In 2014 Stamell won a disability discrimination case against the post office on the grounds that its chip and pin machines were too difficult to reach, for both people with dwarfism and people in wheelchairs.