Kinnaman is known internationally for his television roles as Detective Stephen Holder in AMC's The Killing, Takeshi Kovacs in the first season of Altered Carbon, and Governor Will Conway in the American version of House of Cards.

[4] He grew up with fellow actors Alexander Skarsgård and Noomi Rapace,[14] and spent a year in Del Valle, Texas, as a high school exchange student.

To finance the trips, he worked in various jobs — as a beer factory line worker and roof-sweeper in Norway, and as a bar manager in the French Alps.

[16][17] He then traveled for four to five months at a time over a period of two years in Southeast Asia and South America,[18][19] the latter with fellow Scandinavian actor David Dencik.

[1][16] While studying at drama school, Kinnaman featured in several films such as Hannah med H and God Save the King (Swedish: Tjenare kungen).

[28][24] Although Kinnaman said that he is eager to work and become recognized in the U.S., he added that "I absolutely don't feel that I have to take any role that I can get just because it is the United States.

[28] In 2012, Kinnaman reunited with Easy Money director Daniel Espinosa in the latter's Hollywood debut, Safe House,[35] and also starred in the indie film Lola Versus.

[37] In 2016, Kinnaman played Rick Flag in the Warner Bros. film adaptation of DC Comics anti-hero team Suicide Squad, directed by David Ayer.

[40] He also starred in the independent drama-thriller film Edge of Winter, in which he plays Elliot Baker, a father of two who takes his children on a shooting trip that goes wrong.

[41] Between 2016 and 2019, Kinnaman worked on 4 different original productions of streaming television networks such as Netflix, Amazon Prime Video and Apple TV+.

Since 2019, Kinnaman starred as NASA astronaut Ed Baldwin in the Apple TV+ original science fiction space drama series For All Mankind.

He underwent surgery prior to the filming of Altered Carbon, inserting two metal bars to push the sternum outward in order to correct the deformity.

On 6 August 2021, Kinnaman filed and was granted a temporary restraining order against Gabriella Magnusson, whom he alleged was threatening him in an attempt to extort him after they had been in a brief romantic relationship in late 2018.