The 'Need You Now' singer, who performs with Charles Kelley and Dave Haywood in the country group, told People that she is planning to marry drummer boyfriend Chris Tyrell.
Tyrell is reported to have popped the question while the couple were watching the sun set over a lake in East Tennessee over the holiday weekend.
She told the magazine: "Chris proposed exactly the way I've always dreamed... We feel so blessed by God that he sent us each other and we are looking so forward to forever together!"
The couple also confirmed the news on the official Lady Antebellum Twitter feed with the message: "It's official... Hillary is engaged!"
Scott and Tyrell met while touring with Tim McGraw in 2010.
The Grammy Award-winning Lady Antebellum are currently touring and preparing for the release of their new album, Own The Night, on September 13. The new record has already spawned the song 'Just A Kiss'.
Discussing the new project back in June, Kelley told Billboard: "We're just excited. With the first single debuting in the top ten, we never expected that, so hopefully off to a good start. You never know until it gets out there with the fans. We feel good about it, but they'll let us know if they like it or not."
Watch the video for Lady Antebellum's 'Need You Now' below: