Why Justin Bieber Attended A-List Halloween Party Without Wife Hailey Bieber

The couple celebrated their fifth anniversary last month.

Justin Bieber had a solo night out. On Friday, the 29-year-old singer stepped out for the Casamigos Halloween party in Los Angeles, without his wife, Hailey Bieber, by his side.

An eyewitness tells ET that Justin attended the soirée by himself "because he wanted to enjoy some time with friends."

Matt Winkelmeyer/Getty Images for Casamigos

Justin, who was dressed in flippers and wearing a snorkel, "had a great time and looked like he was in a relaxed and happy mood," according to the eyewitness.

Michael Kovac/Getty Images for Casamigos

"He was taking photos and videos and singing and dancing throughout the night, even to his own song, 'Despacito' at one point," the eyewitness says of Justin, who also posed with FINNEAS during the event. "He also encouraged other partygoers to dance and was very friendly."

Matt Winkelmeyer/Getty Images for Casamigos

The solo outing came the month after Justin and Hailey celebrated their fifth wedding anniversary

"To the most precious, my beloved. 5 years. You have captivated my heart. I know from the depths of my soul down to my bones that this journey with you will only exceed our wildest expectations," Justin wrote to Hailey, 26, on Instagram. "So let’s keep dreaming big baby. Cheers to forever and ever. I love you with every fiber of my being."

Watch the video below for more on the couple.

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