By the age of 13 she was on the books of the Studio Search Agency on the Gold Coast, with her first roles being the Australian telemovies The Flood: Who Will Save Our Children? in 1993 and Official Denial in 1994.

It was not until Holly began her regular television career in 1995 on the Logie Award winning children’s program Agro's Cartoon Connection that she began to receive recognition. She would later host The Looney Tunes Show in a more adult style, along with World's Craziest Videos and various shows for Foxtel. Holly was ranked 5th (2000) and 29th (2001) in FHM's Australia's 100 Sexiest Women.

On 1 June 2005, She received a Film Award for 'Best Actress – Feature Film' at the New York Film & Video Festival for her portrayal of "Geraldine" in the Australian film The Crop. The movie also won 'Best International Feature'.

Holly became engaged to marketing executive Paul Ford in Venice in 2005 and they married on 11 February 2006 in Manly, Sydney. They exchanged vows in the Cardinal Cerretti Memorial Chapel, in the grounds of St Patrick's and overlooking the ocean.

In 2008, Holly voiced the title character in the ABC children's series CJ the DJ which has screened in Australia from late 2009 to early 2010. Holly played the female lead Tara in the feature film Sinbad and the Minotaur (2011).

Holly gave birth to their son, Levi Harper Ford, at the Royal North Shore Private Hospital on 16 July 2009. On 20 July 2012 Holly gave birth to the couple second child, a daughter Willow Jade Ford.

In July 2010, Holly climbed Mount Kilimanjaro in Africa for a charity trek, whereby she raised $50,000 for the Humpty Dumpty Foundation, a worthy cause that helps sick children. She had a near death experience having contracted pulmonary edema caused by the high altitude but is in good health now.