"I have always dreamed about playing in the NBA," Hayes said in a statement. "Now that I have the chance to realize that dream, I would like to pursue that opportunity."
The 6-foot-11 Hayes, who shot 72.8 percent from the field while averaging 10.0 points, 5.0 rebounds and 2.22 blocks per game this season, is ranked No. 9 in the ESPN 100 among NBA draft prospects. He said he would be hiring an agent.
"I'm really proud of Jaxson for the tremendous attitude he's demonstrated all year and the unprecedented growth that he's made," Texas coach Shaka Smart said. "He'll always be a part of our Longhorn Basketball family, and we look forward to supporting him in the next steps of his journey."
Hayes did not play during the Longhorns' run to the NIT championship after suffering a leg injury, which won't require surgery. He wasn't a starter for his Cincinnati high school team until his senior year and wasn't even rated a top-100 recruit when he signed with Texas, but his athleticism and quick development in college had NBA scouts eyeing him almost immediately.
"I'm so appreciative of Coach Shaka Smart for pushing me every day to improve and mature, both on the basketball court and as a person," Hayes said. "Thank you to all the Longhorn fans and the people of Cincinnati who have been there cheering me on the whole way."
A new NCAA rule allows a player who has declared for the draft to return to school even if he has enlisted the services of an agent to help him test his professional prospects. There are several stipulations attached, and if the player returns to school, he must end the relationship with the agent. The deadline to pull out of the draft is May 29.
The Associated Press contributed to this report.