The 25-year-old singer did so with the help of the wristbands given to fans attending the shows on her "1989" tour, reported Ace Showbiz.
As reported by local news station WBRZ, the three teens were Elizabeth Dazzio, her sister Caroline and a friend. They were driving home from the second night of Swift's show in Baton Rouge, Louisiana's LSU Tiger Stadium when Dazzio fell asleep behind the wheel and crashed the vehicle.
Dazzio was unconscious while the two other girls were trapped inside the wreckage.
A woman eventually noticed the light and pulled over to help the girls and called 911. Dazzio was rushed to the hospital and is expected to make a full recovery.
Swift shared the story on Twitter and expressed gratitude that the three girls were okay. "This is unreal. I'm so happy they're okay," she wrote.