"We’d LOVE to tell you who this is … But we’re going to make you wait a few more days. Any guesses? #DWTS," they captioned the snapshot.
The full lineup will be announced on Good Morning America on Wednesday, August 21, ahead of the premiere on Monday, September 16.
The show teased their latest addition by posting a pic of the mystery contestant's arm on Instagram on Saturday, August 17.
Are you excited Hannah is competing on DWTS? Sound off in the comments below!
Clever fans did some digging and discovered that Hannah's arm freckles matched the ones in the teaser pic.
"This is def Hannah B. her hand freckles confirm it !!!!!" one fan wrote in the comments section. "I can confirm this is Hannah B. because of the beauty marks on her neck and right shoulder," another added.