Davidson found his way into show business when as a regular in a pub in Woolwich, he undertook an act after the regular comedian had not turned up. He then became a regular on the London comedy circuit, and first auditioned for Opportunity Knocks in 1975, unsuccessfully; he was told by Hughie Green to “go away”. His audition for New Faces was more successful, and he proceeded to win the show by one point, and then to come second in the overall contest.

Davidson appeared on an edition of the BBC1 series Seaside Special, shown on 20 August 1977, hosted by Tony Blackburn and David Hamilton. The Stage’s reviewer, Martyn Wade, was not impressed: “comedian Jim Davidson had already won first prize for lack of taste with crude racist jokes tracing the adventures of a black man whose nickname was Chalky and whose other names included Toilet-Roll. ‘Day-light come and I gotta sign on’ is a representative line from Mr Davidson’s act.”

Davidson has appeared in the UK singles chart under his own name with the double A-sided “White Christmas”/”Too Risky”. It peaked at No. 52 in December 1980.

“Sinderella” 1995 (also sold on Video) “Boobs in the Wood” 1999 (also on video/DVD) “Sinderella Comes Again” 2004 (DVD) “Sinderella 2: Scottish Romp” 2015, production cut short due to poor sales

Davidson is a Freemason and a long-standing member of the Westminster City Council Lodge No 2882. He was formerly also a member of the Chelsea Lodge No 3098 (whose members are all entertainers) but has resigned; he was the founding Worshipful Master of British Forces Foundation Lodge No 9725 on its formation in 2000.

In 2002, Davidson was escorted from the grounds of the Marriott Bristol Royal Hotel, after it was alleged that he had become confrontational and abusive to staff.

Davidson has several business interests. He set up a company which bought or leased several seaside theatres or piers, including the Winter Gardens building in Great Yarmouth, which was converted into a nightclub. He lost £700,000 on a pantomime production of Dick Whittington and after a meeting with the Inland Revenue in 2003, he sold the company.

On 27 August 2003, after a meeting with the Inland Revenue, Davidson claimed he spent £10,000 a week on back taxes, commission to agents, maintenance and school fees, and a £2.2 million mortgage: “My problem is money – I used to earn five times as much as I do now, but I still pay the same maintenance, school fees and commission to agents,” he told Radio Times magazine.

In October 2003, Davidson refused to go on stage in Plymouth because he objected to wheelchair users in the front row. A spokesman for the Plymouth Pavilions, where he was performing as part of a national tour, said: “Jim Davidson apparently took exception to a number of wheelchair users in the front stalls of the Pavilions Arena. Mr Davidson cited the fact that a proportion of his act was aimed at disabled customers and that he would be unable to perform under these circumstances.” In a statement Davidson explained he “took the mick” out of everyone in the front row of his shows. “As all the people in the front row were in wheelchairs I feared it would appear I was specifically targeting disabled people. I asked if just some would mind moving. Much of my act depends upon audience reaction and in fact one part of the show involves getting the audience to gang up against the front row.”

Laurence Clark, himself a wheelchair user, in response performed a show called ‘The Jim Davidson Guide to Equality’ at the Edinburgh Festival Fringe in 2004. Clark refused to perform the show if Jim Davidson was in his audience. Journalist Martin Fletcher describes Davidson as “extraordinarily foul-mouthed, racist, and sexist” and a “throwback”; whilst quoting television critic Garry Bushell calling Davidson a “family entertainer”.

In 2004, comedian Jimmy Carr threatened legal action against Davidson, accusing him of having plagiarised some of his comic material. Davidson responded by saying the claims were ‘ridiculous’, and no further action was taken.

In March 2004, Davidson, a Conservative supporter, publicly left the United Kingdom for the tax-free haven of Dubai, UAE in protest at the Labour government, although it was also noted by HMRC at the time that his move coincided with an unpaid tax bill of approximately £700,000. At the time, he declared that “I may as well go to Dubai and be an ethnic minority there than wait five years till I become one here.” He moved back to the UK after living in Dubai for five years. He has also expressed sympathy for UKIP leader Nigel Farage, describing the party as “the Jim Davidson of the political world”. He once again moved to Dubai after being accused of sexual offences.

In 2006, for the first time in 14 years, he refused to play Great Yarmouth, stating that the resort was “full of overweight people in flip-flops and fat children of all colours and no class”. The inhabitants of the town took this as a personal affront, although he said he was referring to tourists.

On 6 July 2006, having failed to keep up payments on a £1.4 million back tax bill that he had reduced to £700,000, Davidson was declared bankrupt.

In October 2006, he was again accused of making insensitive jokes about cancer sufferers, blind people, a woman in a wheelchair, and the recent trial over the murder of Damilola Taylor, prompting a woman to walk out of the show in disgust. Davidson vehemently denied the charge, claiming that jokes about blind people and cancer sufferers would have merited a “mass walkout”. He also said the comments about the Damilola Taylor trial were taken out of context: “My actual remark was that I thought the killers should be locked away forever. And if she objects to that then that is her prerogative.” Davidson was also quoted as saying “If what I was saying was true I would have got up and left myself”.

Davidson became known for Big Break (1991–2002) and as the third host of The Generation Game (1995–2002), as the successor to Bruce Forsyth and Larry Grayson. In September 2007, Davidson appeared in the third series of Hell’s Kitchen (2007) in the UK, and in May 2008 he appeared in the BBC’s Comedy Map of Britain.

In September 2007, Davidson participated in the celebrity reality TV programme Hell’s Kitchen. During his time on the show, Davidson attracted negative media attention over what was identified as homophobic bullying towards TV presenter and openly gay contestant Brian Dowling. Davidson asked Dowling, “Are you on our side?” when referring to whether or not he would be participating for the boys’ or girls’ team. Davidson used the word “shirt-lifters” in front of him, and was constantly asking if Dowling would like to try on one of “John Virgo’s lovely waistcoats”, which Davidson owns. Davidson later described himself as a “homophobic arsehole”. The programme was broadcast on ITV on 4 September 2007. On 10 September, Davidson was asked to leave Hell’s Kitchen following further problems with Dowling. After Davidson’s exit from the programme, the BBC reported that the broadcasting watchdog Ofcom had received 46 complaints alleging that Davidson had bullied Dowling. Ofcom concluded that nothing unacceptable had happened, but ITV, the channel which had originally broadcast the programme, issued a statement, regretting Davidson’s “unacceptable remarks”.

Davidson again courted controversy in December 2007, when he made a joke about rape victims during a show at the Newark Palace Theatre, in Nottinghamshire. A local paper, the Nottingham Evening Post, stated that: “there were moments when he did stray too far over the line (most notably with a routine on rape).”

Davidson was called on as a character witness to drug trafficker Brian Brendan Wright in 2007. Despite Davidson’s testifying to Wright’s character, the judge concluded that Wright was “a master criminal, manipulative, influential and powerful,” and sentenced him to 30 years in prison.

In 2011, Davidson toured with a play, Stand Up…And Be Counted. The play was about the failing career of a washed-up racist comic. This caused controversy and links made in the media with similarities between the main character and Davidson’s own career. On 18 March 2011, Davidson announced the show was being cancelled because of poor ticket sales. It had visited only four of the 12 planned city destinations. Davidson added that he was still in talks to bring the show to the West End at a later date.

On 2 January 2013, Davidson was set to become a housemate in the eleventh series of Celebrity Big Brother, but was arrested at Heathrow Airport by police officers working on Operation Yewtree. On 3 January 2014, a year after being arrested and without being charged, he became a housemate in the show’s thirteenth series. On 29 January 2014, he left the Big Brother house as the winner.

On 2 January 2013, as Davidson was set to become a housemate in the eleventh series of Celebrity Big Brother, he was arrested at Heathrow Airport by police officers working on Operation Yewtree. On 20 March 2013 he was arrested again over new allegations of sexual offences, however on the 21 August 2013 it was announced that no further action would be taken in relation to the allegations of historic sex abuse, due to insufficient evidence.

On 18 June 2014, Davidson attended the assault trial of former N-Dubz frontman Dappy. “Dappy is a good friend of mine. I don’t know what’s happened in this case but I’m just here to show him my support,” Davidson said. Dappy’s legal team declined Davidson’s offer to serve as a character witness for the singer.

On 21 November 2018, Davidson was caught up in London traffic resulting from Extinction Rebellion protests which blocked a number of London bridges to raise awareness of a claimed lack of action from governments over climate change. Davidson was photographed by the BBC, allegedly shouted at police and was filmed near the front of a blockade driving a large SUV, where he remarked that Jeremy Corbyn (who was not involved) was an “environmental disaster”. Davidson later told Nigel Farage on LBC radio that the reason for his anger had been that the demonstrations had almost prevented him “from getting his pie and mash”.