The 6-foot-2, 225-pound Wartman, who grew up a Penn State fan, told Scout.com via a text he re-committed to the Nittany Lions on Thursday.
The decision was made about a week earlier than his coach, George Howanitz, expected.
"He told me tonight he's staying committed to Penn State," Howanitz said.
It comes a few days after Penn State assistant coaches Ted Roof and Ron Vanderlinden visited Wartman at his school.
"I think sitting down on Tuesday with coach Roof and Vandy (was big)," Howanitz said. "He loved coach Roof's enthusiasm."
Wartman opened his commitment back up after the Jerry Sandusky scandal hit, and he visited Rutgers in early December.
Before making an official visit over the weekend, Wartman spoke about why he chose Penn State in the first place.
"My overall feel for them was it was a special school," he said. "They had everything I liked."
He made more than 300 tackles in his career, and had 16 catches for 408 yards and six scores as a senior.