Bill Westenhofer is an American visual effects supervisor. He worked for Rhythm and Hues Studios until its closure in 2013.

His hometown is Brookfield, Connecticut, where he graduated from Brookfield High School in 1986. He then earned a Bachelor of Science in Computer Science and Engineering from Bucknell University in 1990.

Westenhofer also received his master's degree at the George Washington University School of Engineering and Applied Science in 1995, where he studied the use of dynamics in physically based animation.

In 1994, he joined Rhythm & Hues as a technical director, and Westenhofer's lighting and effects animation work was featured in Batman Forever and numerous commercials. He was promoted to CG supervisor for Speed 2: Cruise Control and continued in that role for Spawn, Mouse Hunt, Kazaam, and Waterworld. His other VFX supervisor credits include Elf, The Rundown, Stuart Little 2, Men in Black II, Cats & Dogs, Along Came a Spider, Frequency, Stuart Little, and Babe: Pig in the City.

In 2005, Westenhofer supervised a team of 400 digital artists on The Chronicles of Narnia: The Lion, the Witch, and the Wardrobe, which was nominated for an Academy Award for Best Visual Effects. Later, he would win both the BAFTA and the Academy Award for the 2007 release The Golden Compass and 2012's Life of Pi in 2013. Westenhofer also worked as a VFX supervisor for Wonder Woman and Black Adam.

His latest work is on Marvel Studios' Captain America: Brave New World.