Thomas Charles Gillis (born July 16, 1968) is an American professional golfer.

Gillis was born in Pontiac, Michigan, and graduated from Lake Orion High School in Lake Orion, Michigan. He turned professional in 1990 after playing collegiate golf at Oakland Community College.

Gillis played on the PGA Tour in 2010 after several years on the Nationwide Tour, and having previously competed on the PGA Tour in 2003 and 2005, and the European Tour from 1998 to 2002. He also played in several PGA and Nationwide Tour events during the 1990s. According to his profile, Gillis has played professional tournaments in 26 different countries.

Gillis won his first event on the Nationwide Tour at the 2009 Nationwide Tour Players Cup. He finished 5th on the money list to earn his 2010 PGA Tour card. In 2010, Gillis finished tied for fifth at the Deutsche Bank Championship. He retained his playing rights for the 2011 season, finishing 76th on the money list. He spent 2014 on the Web.com Tour, but a strong performance in the Finals earned him a place on the PGA Tour for 2015.

His best career finish is a tie for second at the 2012 Honda Classic and a solo second at the 2015 John Deere Classic after a playoff against Jordan Spieth.