Along with other roles and bit parts in television, films, direct-to-video animation, advertising, and video games, he played Peter Shepherd in Jumanji, the original voice of Chip in Beauty and the Beast, one of the original voices for Tails from the Sonic the Hedgehog franchise and Pete Lender in the 1997 film adaptation of The Borrowers.

He is also known for voicing Chip in Disney's Beauty and the Beast as well as Tails in the Saturday morning cartoon series Sonic the Hedgehog.

Pierce provided additional voices in The Busy World of Richard Scarry and appeared with Patty Duke and Melissa Gilbert in the TV film Cries from the Heart/Touch of Truth as an autistic child named Michael.

He has guest-starred on such TV shows including Life Goes On, Roseanne, Herman's Head, Mad About You, Lois & Clark: The New Adventures of Superman, Touched by an Angel, Profiler, Star Trek: Voyager, and voiced the character Nibs in the 2002 film Return to Never Land.

Outside of film-making, Bradley is the co-founder of Pierce & Luna,[3] a cocktail community geared towards bartending education and liquor reviews.