Nathan Fielder was born on May 12, 1983, in Vancouver, British Columbia, to social workers Deb and Eric Fielder. He attended Point Grey Secondary School, where he did improv comedy alongside future star Seth Rogen. Fielder studied business at the University of Victoria, then enrolled in a comedy program at Humber College in Toronto.

Fielder began his career in 2007, writing for Canadian Idol before joining This Hour Has 22 Minutes as a correspondent. In 2013, he co-created and starred in Nathan for You on Comedy Central, playing an off-kilter version of himself. The show offered outlandish advice to real small businesses and ran for four seasons through 2017. Fielder also founded the Holocaust-awareness apparel brand Summit Ice in 2015 and featured it on an episode of Nathan for You.

Fielder followed Nathan for You with HBO’s The Rehearsal in 2022, helping people practice difficult conversations using elaborate sets and hired actors. Its second season, released in 2025, focused on aviation safety and pilot communication. He also co-created and starred in Showtime’s scripted series The Curse in 2023 alongside Emma Stone and Benny Safdie. As of 2026, Fielder continues to write, direct, and host new seasons of The Rehearsal for HBO.