The 20-year-old New Jersey native signed a deal through the 2023 season with an option to extend for two additional seasons.
NYCFC acquired his homegrown priority rights by sending $100,000 in general allocation money to the New York Red Bulls. The Red Bulls will receive additional money if Gloster reaches certain performance benchmarks.
"It's such an honor to be joining New York City FC," Gloster said in a team statement. "I know a lot about the club and it's a team with a good playing style that I feel I fit perfectly into. I'm glad to be back home and it feels amazing to have a team that is really invested in me. Every team that you go to, you learn something new. NYCFC has something great to offer and I hopefully will be able to do my best for this Club."
Gloster, who has been a regular in the United States youth setup, joined NYCFC in Florida for training camp last week. The team is scheduled to open the MLS regular season on April 17 at D.C. United.
Gloster competed in 22 matches for PSV Eindhoven's reserve team, Jong PSV, from 2019-20. Prior to his stint in the Netherlands, Gloster played with the German club Hannover 96 in 2018.
"Chris is a player we're very excited about joining NYCFC," said Ronny Deila, the club's head coach. "He's a highly regarded 20-year-old with a few seasons of experience in Europe at some really good clubs. I enjoy working with young players to help maximize their abilities and Chris is one who we think can come to us and grow into a really good player."