Kielty began his professional career in a comedy club; the Empire Laughs Back along with his friend Jackie Hamilton while he was a psychology student at the Queen's University of Belfast. His fellow student Jackie Hamilton was a BBC producer.
In 1990, Kielty became the winner of Guinness Entertainer of the Year, an event hosted by Sean Mallon in INF Warrenpoint. Later in 1993, he presented the show SUS on UTV. After that, he ran the warm-up act for BBC Northern Ireland programme, Anderson on the Box, which was presented by local personality Gerry Anderson.
However, this show ran only for a year and it was only shown in Northern Ireland, which won him the "Best Newcomer" Award at the 1996 Royal Television Society Awards. Next year, he formed the Belfast-based TV production company Green Inc with TV director Stephen Stewart. They created numerous shows including, The Afternoon Show, Patrick Kielty Almost Live and Ask Rhod Gilbert.
Similarly, he also hosted the opening ceremony of the Special Olympics in Croke Park, Dublin, viewed by 800 million. The show attended by personalities like Nelson Mandela, Muhammed Ali, and U2. In 2006, he hosted a charity show, The Prince's Trust 30th Birthday LIVE along with Kate Thornton, which was aired on ITV television network.
Later, Kietly began working at the Trafalgar Theatre in London’s West End on the drama, A Night in November, written by Northern Irish dramatist Marie Jones. He appeared in the play at the Grand Opera House in Belfast. In the same year, he gave appearance on a British stand-up comedy, Live at the Apollo.
Kielty also presented Sports Relief of 2010 and 2012 together with Fearne Cotton. He also hosted the first series of Channel 4's called Stand Up for the Week, which began in June 2010 and ran for six weeks. After a couple of years, he co-presented a spin-off show This Morning along with Kate Thornton for an episode.
Later, Kielty again joined BBC Northern Ireland to present numerous programmes such as Bad Language, along with Susan Calman and Paul Sinha. After that, he hosted a television documentary Patrick Kielty's Mulholland Drive, story based on the life of William Mulholland and the California Water Wars.
Kietly is the holder of an Irish nationality and also belongs to Irish ethnicity. He married his long-term girlfriend, Cat Deeley on 30 September 2012, in a private ceremony in Rome. The couple blessed with a son, Milo Kietly on 19 January 2016. Presently, he is enjoying his married life with wife, Cat Deeley and with son, Milo. Till date, there is no rumor of their separation or divorce.
Being a television presenter or program host, Kietly earns a decent salary from his professional career. He also appeared on shows for popular media such as BBC and ITV from which he collects a huge amount. As of 2017, his net worth is estimated at $8 million.
Besides, Kietly\s wife Cat Deeley is also a TV presenter and host. She also earns a tremendous amount of money through her professional career. Her lavish lifestyle also binds a point that her net worth is no less than a $1 million.