Janice White and John Nelson are Jesy's parents. She has one older sister named Jade and two brothers named Joseph and Jonathan. Her parents separated when she was very young.
- She dated dancer Jordan Banjo from 2012 till 2014. Jordan is a member of Diversity, a dance group, that won Britain's Got Talent in 2009. He was Jesy's boyfriend until their split sometime in 2013. Eventually they got back together. They broke up again in the end of June 2014 because of their busy schedules. Jesy's bandmate Jade Thirlwall broke up with her boyfriend Sam Craske, a bandmate of Jordan, around the same time.
- She briefly had an romantic encounter with former Union J member, George Shelley. They have denied the rumours of them dating, and he confirmed that they are only friends.
- She's the ex-fiancée of Jake Roche, singer of the band Rixton. She flew to LA to see a concert of theirs in August 2014 and posted a picture and a video with him on her Instagram account. The relationship became official when Jesy posted a picture of them kissing. They got engaged in July 2015. On November 21, 2016, it was confirmed that the couple split up. 
- She briefly had a romantic encounter with the Only Way is Essex star Chris Clark in March 2017, however they split up after a month of dating because Clark believed that his and Jesy's lives were too different.
- She confirmed in late September/early October 2017 that she is dating singer-songwriter and former rapper, Harry James.