She started her broadcasting career in 1984 as a producer on cable channel Music Box and moved on to presenting in 1988 as co-host of the Chris Evans shows on GLR. Her style then and characterised today is based on comedic observation of men.

She and Chris Evans (broadcaster) married each other in 1991. They separated in 1993 and were divorced in 1998.

In 1995 McGiffin was a founding member of the Talk Radio UK team, co-presenting the popular weekday evening show The Rude Awakening with Moz Dee. When the show ended in September 1995 she became the station’s music expert for around six months, hosting her own Friday evening review slot and appearing every week on Jonathan King’s programme. In late 1996 she reappeared on Liberty Radio, co-hosting the breakfast show with Richard Skinner for six months. In 1997 and 1998 she united with Paul Ross and Nick Abbot in varying time slots.

In 1999 she joined London radio station LBC teaming up again with Abbot, who left the station after six months. McGiffin continued to host the show on her own with producer/sidekicks, including Marcus Railton and Jonathan Sanchez until 30 September 2000. She co-hosted phone-in shows on BBC London Live. In 2002, she occasionally teamed up with Abbot on Real Radio.

Between February and July 2006 she was the southern presenter of the Local Radio Company’s night-time talk show North South Divided. Mike Elliott was her northern counterpart. In August 2006 McGiffin returned to LBC 97.3 presenting a Sunday morning show. McGiffin’s weekly views on the world and travel advice in her Travel Clinic ended on 10 February 2008, when she left the station. Throughout the summer of 2012, she regularly reviewed the daily newspapers on This Morning. In August 2013, she entered the Celebrity Big Brother house to compete in the twelfth series, where she finished in fourth place.

In 2010, McGiffin released her autobiography, Oh, Carol!.

In June 2018, it was announced by panellist, Denise Welch that McGiffin would be returning to Loose Women after five years away.