He is a two-time recipient of the Polish Academy Award for Best Actor.

Zamachowski graduated from the actor's faculty of the National Film School in Łódź.

He began his acting career in 1981 and in 1989 had a co-starring role in Part Ten (Thou Shalt Not Covet Thy Neighbor's Goods) of director Krzysztof Kieślowski's film series, Dekalog.

[1] Four years later, Kieślowski cast him as the lead character, "Karol Karol", in Three Colors: White, the second of his acclaimed Three Colors trilogy.

[2] His other notable roles are featured in Kazimierz Kutz's film Colonel Kwiatkowski (1996), Jerzy Hoffman's historical film With Fire and Sword (1999) and Andrzej Wajda's biopic Walesa: Man of Hope (2013).