The British Basketball League Championship, often shortened to the BBL Championship, was the top-level men's professional basketball league in the United Kingdom from 1987 until 2024. The competition was administered by the British Basketball League and comprised 10 teams from both England and Scotland. Each team played a 36-game regular season, from September until April, with the team that finished in first place being crowned as League champions.

Following the end of the regular season, the top eight-placed teams used to advance to the postseason Playoffs tournament to decide the winner of the BBL Playoffs.

The BBL used a franchise system, with no promotion or relegation from other leagues, although several clubs have been elected from the English National Basketball League in recent years.

Since 1972, the English Basketball Association-operated semi-professional National Basketball League provided competition for the country's top basketball clubs. The league started with six clubs, but grew each year to include multiple divisions featuring teams from across England. However, by the mid-1980s, following an increase in the sport's popularity due to coverage from television network Channel 4, the League's foremost clubs – looking to improve the basketball's image through greater professionalism – broke away from the English Basketball Association and formed their own administration. The new organisation, simply called the Basketball League, was established in 1987 and saw a franchise-based set-up where every member would have an equal shareholding and a representative on the League's Board of Directors, and with no promotion or relegation to the lower leagues aiming at increasing the league's stability. The NBL's sponsorship deal from the Carlsberg Group continued with the new organisation and the newly founded Carlsberg League tipped off its inaugural season in 1987. A total of 15 teams took to the floor for the 1987–88 season, with the new League including all 13 former NBL teams present as well as drafting in new entrants Oldham Celtics (promoted from NBL Division 2) and Livingston (elected from the Scottish National League). The new league continued the NBL's policy of allowing only two import players to be registered per team. Portsmouth were the early pace-setters and pipped Kingston to the first regular-season League title but it was underdogs Livingston, the only member based outside England, that claimed the first Championship thanks to an 81–72 victory over Portsmouth in the Play-off Final.

Portsmouth's dominance was short-lived however and after a failed attempt to relocate to Reading, the franchise withdrew from the League in 1988. This was the beginning of a membership crisis for the Carlsberg League, with no fewer than seven teams withdrawing from the competition by the start of the 1989–90 season. With a lack of teams, the League opened up for expansion and brought in the newly rebranded London Docklands team along with Cheshire Jets and Worthing Bears from the NBL, whilst readmitting Birmingham Bullets and Hemel Royals over the next couple of seasons. In 1990, the league was rebranded as the Carlsberg League Division One, after the Carlsberg Group decided to extend its sponsorship to the lower leagues. Kingston dominated the League throughout its early years and under the guidance of Coach Kevin Cadle – the most successful coach in British Basketball history – netted four consecutive regular season and Championship titles from 1989 (as Glasgow Rangers) to 1992.

In 1993, the competition was rebranded again due to new sponsorship deal from Budweiser, thus becoming the Budweiser Basketball League. The addition of Sheffield Sharks (from the NBL) and the London-based Leopards in 1994 ushered in a new era for the League, with both teams utilising multimillion-pound arenas to stage home games. It was a huge step away from the traditional, small sports centre venues that were commonplace throughout the League (though London Docklands briefly used London Arena for home games). With financial backing from the Chrysalis Group, Sheffield stormed to their first League title in 1994–95 season – their rookie season. Following the demise of Kingston, who had since moved to Guildford to become the Guildford Kings, Worthing made their mark in history with three back-to-back Play-off Finals victories from 1993 to 1995. In 1995, the Budweiser League secured a deal with BSkyB to broadcast games live on its Sky Sports platform, which brought a greater following and popularity to the League. To increase playing standards and game quality, the League amended its rules a year later to allow teams to include five imported players on their roster.

By 1996, the Budweiser League had become more stable and comprised 13 teams, all of which were based in England and five of which were located in and around London (Crystal Palace, Hemel Royals, Leopards, London Towers and Thames Valley Tigers). The capital city enjoyed huge success throughout this period with Towers taking the 1996 League crown and Leopards scoring back-to-back League titles in 1997 and 1998 – where they won via head-to-head results over second placed Birmingham Bullets after both teams finished with 58 points. The spell of dominance from the South was broken by Birmingham's two Championship Final's victories in 1996 and 1998, against the Towers and Thames Valley Tigers respectively. The 1998–99 season saw a new addition to the League with the expansion of Edinburgh Rocks, who became the League's first Scottish-based team since Glasgow Rangers' and Livingston's participation in 1989. The 1999 Budweiser League title came down to a final game between title-chasing rivals Sheffield and Manchester Giants in front of more than 11,000 fans at Manchester's MEN Arena. With both teams tied on points at the top of the League table, and tied at 85–85 with just 3.5 seconds left in the game, Terrell Myers' last-gasp 18-foot buzzer-beating jump-shot claimed the regular season title for Sheffield. However it was the third-seed London Towers who went all the way in the post-season play-offs and took home the Championship crown.

Another change of sponsorship in 1999 saw the competition renamed as the Dairylea Dunkers Championship, whilst the League radically changed its structure to incorporate a conference-based system. The League's 13 teams were geographically divided into two conferences – seven teams in the North and six teams in the South – with the top four-placed teams in each conference advancing to the play-offs. Towers had dominated the South, whilst Giants gained revenge on Sheffield, pipping them to the Northern Conference crown. The Northern and Southern winner's were kept apart throughout the play-offs until the Final, where Manchester went on to beat Birmingham for the post-season title. The new millennium saw yet another name change as the competition was rebranded as the British Basketball League Championship following the end of Darylea's sponsorship in 2000 and the 2000–01 season saw one of the biggest upsets in BBL history as Leicester Riders, who finished with a 17–19 record in the regular season and were the lowest seeded team in the play-offs, went all the way to take the Championship silverware with a 75–84 in the Final over Sheffield. Following that season the League's TV broadcasting deal transferred from BSkyB to ITV Digital in a three-year contract agreement. Just months later the Manchester Giants became the first franchise to be removed from the competition by League officials due to unfulfilling a fixture and a lack of finance.^{[citation needed]}