Will Byler and Bailee Ackerman Byler were both students at Sam Houston State University. Their deaths were first reported by the student newspaper.
The crash occurred near Uvalde, about 85 miles (135km) west of San Antonio.
On social media, wedding attendees have been posting their condolences in the captions of wedding photos.
"I'm absolutely devastated!" wrote one friend on Facebook, adding that the pilot of the aircraft was also killed.