Decked out in a babydoll Mrs. Claus dress, Halsey closed the night with an unforgettable, touching performance.
"My dad grew up in Boston," Halsey opened up, "which means a lot of my family is here and I spent every summer and every christmas, and a lot of birthdays in Quincy, Massachusetts."
Unfortunately, tragedy struck earlier this week.
"My great-grandmother was from Quincy, and two days ago, she passed away," Halsey shared, tearing up.
"But because I was coming here, to play Jingle Ball, I was lucky enough to be there for my family during that time."
"But this isn't a sad story. It's a happy one, I promise."
"Because my grandmother always liked it the best when I would just sing, just me and a guitar. That was her favorite way of hearing me sing."
"So while I have you guys in this room I was wondering if I could do that for her. Is that ok?"
"Most of you won't know the words and that's ok," Halsey admitted, "cause you don't need to to participate in this song. All you need to do is take out your phone and hold up your light."
"And if you're with somebody that you love, hold them tight while you do it."
Then, in a touching tribute, the "Nightmare" singer dropped the pyrotechnics and stage effects to deliver a stripped down performance of her song, "Finally."