Julianne Alexandra Hough was born on July 20, 1988, in Orem, Utah, the youngest of five children in a Mormon family to parents Bruce and Marianne Hough.

Her father served twice as chairman of the Utah Republican Party and ran for Utah's 2nd congressional district in 2023, while her brother Derek Hough is also a renowned professional dancer, and all four of her grandparents were dancers.

She began formal dance training at the Center Stage Performing Arts Studio in Orem, competing from age nine, and at ten moved to London with Derek during her parents' divorce to train under coaches Corky and Shirley Ballas at the Italia Conti Academy of Theatre Arts, where she studied various dance forms, song, theatre, and gymnastics.​

At fifteen, Julianne Hough became the youngest dancer and only American to win both Junior World Latin Champion and International Latin Youth Champion at the Blackpool Dance Festival. She returned to the U.S., attending Las Vegas Academy and Alta High School, and appeared as a Million Dollar Dancer on the 2006 ABC show Show Me the Money.

In 2007, she joined Dancing with the Stars as a professional dancer, winning seasons four with Apolo Ohno and five with Hélio Castroneves, becoming the youngest pro to win at that time, and earning three Primetime Emmy nominations, including a 2015 win shared with Derek.​

Julianne Hough pursued music with her 2007 single "Will You Dance With Me" and self-titled debut country album in 2008, which topped the Billboard Country Albums chart and reached number three on the Billboard 200, yielding singles like "That Song in My Head" and earning her 2009 Academy of Country Music Awards for Top New Female Vocalist and Top New Artist.

Her acting career began with an uncredited role in the 2001 film Harry Potter and the Philosopher's Stone, followed by major parts in Burlesque (2010), Footloose (2011) as Ariel Moore, Rock of Ages (2012) as Sherrie Christian, and Safe Haven (2013).​

She returned to Dancing with the Stars as a judge from 2014 to 2017, made her Broadway debut in 2022 as Dusty in POTUS: Or, Behind Every Great Dumbass Are Seven Women Trying to Keep Him Alive, hosted Tony Awards pre-shows in 2022-2024, and rejoined Dancing with the Stars in 2023 as co-host with Alfonso Ribeiro.

Julianne Hough portrayed Sandy in the 2016 Grease Live! and judged America's Got Talent's 14th season, while also co-owning the Fresh Vine Wine brand with Nina Dobrev and founding Canary House Productions.​

Personally, Julianne Hough dated country singer Chuck Wicks, Ryan Seacrest, and NHL player Brooks Laich, whom she married in 2017 before their divorce finalized in 2022; she was diagnosed with endometriosis in 2008 and faced controversy over a 2013 Halloween costume.

Though raised Mormon, she no longer practices the faith, and with Derek toured as Move Live On Tour in 2014-2015 and Move Beyond in 2017.​