It's been a whirlwind year for the lovebirds.
The 22-year-old model took to Instagram on Sunday to mark the occasion with a stunning shot of herself and Justin, alongside a heartwarming note to the pop star. The couple secretly tied the knot at a New York City courthouse in September 2018, two months after getting engaged.
"[One] year ago I said yes to being your best friend for life, and today I have never loved you more," Hailey wrote. "Life gets more beautiful everyday because of you, my heart belongs to you forever. Here’s to learning and growing together.. ❤️?."
"Justin decided to propose to Hailey... in the Bahamas, but had been planning to ask her for a couple weeks now. The ring is gorgeous and Hailey is over the moon with joy. The two can’t stop telling their friends and family how excited they are for their journey together," the source said at the time.
Hailey opened up about Justin's proposal to Vogue in February, telling the outlet that the event was the biggest surprise of her life.
"We were on a trip to the Bahamas and we were alone in a house, just the two of us," she gushed. "It was very special."
Justin and Hailey first dated in 2015, and in the year since they got back together, they've found themselves defending their relationship to fans.
"We're adults that have better things to do than waste time explaining something just so you can stop your delusional fantasies," Hailey wrote on Instagram last month. "I'm not gonna sit here and let obsessive strangers try to tell me about my own husband, you wanna talk about somebodies husband then get ur own. G'night!!"
See more on the pair in the video below.