"There's no doubt in my mind he'll be on the roster," Hornacek said Thursday, according to multiple outlets.
The Knicks have received calls from teams looking to trade for Porzingis after the 21-year-old skipped out on exit meetings, per ESPN sources.
Porzingis skipped the meeting due to frustration with the direction of the franchise, per team sources. The Knicks have lost a combined 101 games in Porzingis' first two NBA seasons.
Porzingis hasn't had direct contact with the club since he skipped the exit meeting. He left for his home country of Latvia last month and plans to remain there for much of the offseason, playing for the Latvian national team in the European Championships.
Hornacek said he texted Porzingis but didn't hear back from him after the meeting, according to reports. But the coach expressed confidence that Porzingis would be back with the team next season.
"We expect him back. I think everything's going to be just fine when we get back," the coach told reporters at the combine.
Kristaps Porzingis' brother, Janis Porzingis, said in an interview with ESPN on Wednesday that the Knicks' forward wishes to remain in New York but also wants the club to create an environment conducive to player development and winning.
His brother made it clear that if traded, Porzingis intends to play out his contract and test free agency.
"Kris wants to stay in New York; he feels at home there. There is no question about it. The only thing he wants is for the Knicks to create an environment where he can develop and grow as a player and win," Janis Porzingis said. "If he were traded, he would play out his contract and head into free agency, where he can choose his own destiny."
Janis Porzingis is a certified agent working for the agency of Andy Miller, who is Kristaps' agent.
It is unclear if the calls from opposing teams looking to trade for Porzingis led to any substantial discussions with the Knicks. Hornacek addressed Porzingis' decision to skip the exit meeting while speaking to reporters in Chicago.
"He decided not to come to the meeting," Hornacek said, according to reports. "It would've been a great opportunity to talk about what he sees, but we figure it's a long summer. We'll end up talking to him, and all that stuff coming into next year will be fine.
"I don't know if it's disappointed. Guys make decisions and live with those decisions. It just would've been a good opportunity to talk about what the concerns are moving forward. You can't do anything about the past. That's the big thing. Whatever happened and went on, you can't dwell on it. You got to learn from it and make the proper adjustments to move forward."
Hornacek added he may go to Europe in late August and early September, which would give him the opportunity to meet with Porzingis and visit with fellow Knicks Willy Hernangomez and Mindaugas Kuzminskas, who also plan to play in the tournament.
ESPN's Ian Begley contributed to this report.