2018–19 British Basketball League season

The 2018–19 BBL season was the 32nd campaign of the British Basketball League since the league's establishment in 1987. The season featured 12 teams from across England and Scotland.

The Leicester Riders were the three-time defending regular season champions, but were unable to defend that title as the London Lions achieved their first regular season title; a 99–80 victory at the Newcastle Eagles, on 26 April 2019, was enough for the Lions to have an unassailable lead ahead of the Riders. It was the Lions' second trophy of the season, after they defeated the Glasgow Rocks in the BBL Cup final.

The Lions were beaten in the playoff quarter-finals by the eighth-seeded Plymouth Raiders, who overturned a six-point deficit from the first leg into an eight-point aggregate victory. The Raiders were then beaten by the Riders in the semi-finals, before the Riders won their third consecutive playoff final with a 93–61 victory over the London City Royals, who in their first season in the league, had won the BBL Trophy in overtime against the Lions.

Teams
The newly formed London City Royals replaced Leeds Force.

Regular season
The winners of the Regular season are considered as national champions. The London Lions achieved their first regular season title with a 99–80 victory over the Newcastle Eagles at the Eagles Community Arena on 26 April 2019.

Quarterfinals
The quarterfinal matchups and tip-off times were confirmed by the league, on 28 April 2019.

British clubs in European competitions
British clubs returned to European competitions eleven years after their last participation.