Police on Thursday said 18-year-old DeAndre "Dre" Tatum died of his injuries. He was the last of the victims who had remained in critical condition at the hospital.
Tatum was one of the victims hit by 21-year-old Rashad Owens, who was allegedly fleeing from Austin police. The driver crashed through a barrier and into a street full of festivalgoers on March 13.
Austin resident Jamie West, 27, and Dutchman Steven Craenmehr, 35, were killed at the scene. Sandy Le, 26, died of her injuries a few days after the crash. More than 20 others were injured.
Owens, an aspiring rapper from Killeen, Texas, is charged with capital murder and aggravated assault with a motor vehicle, and prosecutors are expected to seek additional charges against him from a grand jury.
The Associated Press contributed to this report.