He is best known for his roles as Simon Grim in three Hal Hartley films: Henry Fool (1997), Fay Grim (2006) and Ned Rifle (2014), Robert Crumb in American Splendor (2003), Dr. Thaddeus "Rusty" Venture on the animated series The Venture Bros. (2003–2023), Grant Grunderschmidt on Review (2014–2017), and Arthur Tack on Difficult People (2015–2017).

He has also been acclaimed for his acting in the films Henry Fool and American Splendor, in the latter of which he played legendary cartoonist R.

From 2015 to 2017, Urbaniak played Arthur Tack for all three seasons of the critically-acclaimed Hulu comedy series Difficult People, opposite Julie Klausner and Billy Eichner.

In 2018, Urbaniak played the recurring role of Special Agent Owen Quinn on the CBS series Criminal Minds.

In 2022, Urbaniak played the Principal of Grand View High School in the film The Fabelmans, directed by Steven Spielberg.