Indelicato was born in Philadelphia, Pennsylvania to Lynn and Mark Indelicato, Sr. He is three quarters Italian and one quarter Puerto Rican descent. He was trained at The Actors Center in Philadelphia and began acting at the age of eight at Philadelphia's Walnut Street Theater and has appeared in numerous national television commercials, the CBS television series Hack, Chapelle's Show and was a regular cast member on ABC's Ugly Betty all four seasons. He also attended the Professional Performing Arts School in New York City, New York before moving back to Los Angeles, California. Indelicato was also featured in an episode of The Suite Life of Zack and Cody in a special High School Musical-themed episode. On October 27, 2008, Indelicato portrayed the part of Boq for the 5th Anniversary of Wicked Day on Broadway in New York City as well. He performed again at the Gershwin Theatre on February 28, 2009 for the "Defying Inequality" benefit. Indelicato also starred as the Artful Dodger in CLO production of Oliver! in Pittsburgh, Pennsylvania.
Indelicato is a gay rights activist and is openly gay. He was even featured on a Dr. Phil segment about teenagers who were being bullied after coming out. He shared his experience about him receiving death threats and verbal abuse from his role on Ugly Betty with the teens.