The 27-year-old Ignorance singer and the guitarist, 34, were married at the Franklin Theater.
Bosses at New Found Glory's record label Hopeless Records confirmed the news in a tweet, writing, "Congratulations Chad & Hayley!!!" alongside a photograph of the happy couple outside the city's Puckett's Gro. restaurant.
The newlyweds posted shots from the big day on social media - one image featured a photo of the pair's doughnut-style wedding cake.
Orange-haired Williams was an unconventional bride, wearing a short-sleeved fitted bodice with a ballgown skirt, before changing into a T-shirt with her new husband's name in red on the front.
She captioned one of the shots: "Hayley and chads wedding - 20/02/16."
The couple started dating in 2008 and became engaged in December, 2014.
Before dating Chad, Hayley, who has performed with her new husband's side project What’s Eating Gilbert, romanced former bandmates Josh and Zac Farro.