Thanks to her actor father and uncles, the model has a pretty famous surname of her own but she's dropped it in honour of her husband Justin Bieber.
It seems like Hailey is really embracing her married life with Justin Bieber!
The 21-year-old made this step just a day after she also rocked a denim jacket emblazoned with her new last name at a party!
In September, months after announcing their engagement, rumors swirled that Bieber and Baldwin were married and were spotted at the New York City Marriage Bureau.
People promptly reported that the couple had legally tied the knot, but they were holding off on considering it official until they could bask in a religious celebration "in front of God and everyone they love".
Most recently, Justin hopped on Instagram to post a picture of him and Hailey together.
Hours before the surprise announcement, Justin confirmed their relationship status on Instagram with a couple photo he captioned: "My awesome wife".
Justin can not stop gushing over his wife on social media, posting an adorable photo of each other holding hands.
The couple are planning to make their marriage meaningful in the eyes of God through a second, formal wedding in a church in the near future. Nona Melkoni, who said she had dinner next to them at Joan's on Third in Studio City, California, back in October.