Cartlidge was born in London to an English father and a German Jewish refugee mother. She was educated at the Parliament Hill School for Girls in Camden. Her work on Manchevski’s Before the Rain, and on No Man’s Land made her well known in the Balkans and Bosnia-Herzogovina. Sophie, in Mike Leigh’s Naked, was her first leading role. Leigh and Cartlidge worked together twice more after Naked, on Career Girls, playing Hannah at both 20 and 30, and Topsy Turvy, playing a madame in the scene where Sullivan visits a Paris brothel. She was due to play the lead role in Polish director Lech Majewski’s 2004 film The Garden of Earthly Delights—that of an art historian dying of cancer—but she left shortly before production began. Cartlidge died at age 41, due to complications from pneumonia and septicaemia, stemming from a pheochromocytoma.

The impact of Cartlidge’s sudden death saw the creation of the Katrin Cartlidge Foundation by the trustees Mike Leigh, Peter Gevisser, Simon McBurney, Chris Simon and Cat Villiers. The patrons include Lars von Trier and Cartlidge’s sister Michelle. Established at the Sarajevo Film Festival, an annual bursary is awarded by “an elected curator, chosen by the (Foundation) Trustees from a wide and eclectic number of Katrin Cartlidge’s friends and colleagues…(to) a new creative voice… While the new talent nominated each year will be a filmmaker, it is anticipated that the choices will be as varied and extraordinary as Katrin’s own choice of filmmakers and friends from across the arts.” Mike Leigh: ” She took to the improvisation and character work instantly, easily and with extraordinary commitment and imagination. Other than in the Royal Court Young Peoples Theatre, she had had no formal training, but you would never have guessed it. (Drama Centre London turned her down, and that put her off). She often talked to me about [a] move into directing. I am in no doubt that we have lost not only one of our greatest actors but also one of the most interesting new directors of the future.”  Following her death, British singer Morrissey dedicated a performance of his song “Late Night, Maudlin Street” at the Royal Albert Hall to Cartlidge, describing her as ‘brilliant person and fantastic actor’.