For three years when Hagan was a small child, she and her parents lived in a council house in Grove Hill, a housing estate in Middlesbrough. She was enrolled by her mother in a private nursery. When Hagan was three years old, the council house she lived in was burgled during the night. Sometime later, her mother witnessed three people inside a burning vehicle, and made plans to move elsewhere the following day. Ultimately, the family moved to Thornaby-on-Tees, and at the age of four, Hagan was enrolled at St Joseph's RC primary.
Before Geordie Shore, Holly worked for HM Revenue and Customs and in sales at a Santander call centre, in hopes of launching a career as a glamour model. After applying for, and securing a place on the show she eventually quit her job.
Holly has featured in many men's magazines including Nuts with a photoshoot with fellow cast mate Vicky Pattison as well as by herself on several occasions. She has also appeared on the cover of both the UK's FHM and Loaded. In July 2012 she posed naked for a photoshoot with the magazine. This was her first naked photoshoot. In August 2012 Hagan appeared nude in a photoshoots for OK! and Heat showcasing her three stone weight loss.
2011–present: Geordie Shore
Holly Hagan began her public career on MTV series Geordie Shore in 2011 at the age of eighteen. Her opening statement on the show was "I'm fit, I'm flirty and I've got double F's". She has starred in all twelve series of the show including the Big Birthday Battle, featuring in every episode except episode four of the first season. In the seventh series, her most notable 'clash' was with newcomer Marnie Simpson and the two got into an altercation. In an interview with UK Now Magazine, Holly said the two of them 'don't speak'. However, they are now friends. Also in the seventh season, Holly celebrated her 21st birthday. In Series 9 Holly began romance with Kyle Christie who is also a member of the Geordie Shore cast. Holly enters the house in season 10 with Kyle. In October they made their relationship official and were boyfriend and girlfriend, before a dramatic break-up in Series 11 of the show, shown between October and December 2015.. Holly left Geordie Shore during Series 12, following an argument with co-star Charlotte Crosby. She returned the next episode and announced to everyone she was back with Kyle. However, in the Big Birthday Battle series she announced that she was single. Kyle did return but they didn't get back together but remained friends.
In 2014, Hagan released a remixed cover version of Milkshake.
In April 2016, Holly and her ex-boyfriend, co star Kyle Christie star in MTV's new show Car Crash Couples.
She has also released an autobiography titled "Holly Hagan: Not quite a Geordie book."
- 2012: "VIP, Who Cares!"
- 2014: "Milkshake"