The Scottish League Cup, also known as the Premier Sports Cup for sponsorship reasons, is a football competition open to all Scottish Professional Football League (SPFL) clubs. First held in 1946–47, it is the oldest national League cup in existence. The competition had a straight knockout format but became a group and knockout competition from 2016–17.

Rangers are the record holders of the cup, winning 28 times. Celtic are the current holders, winning their 22nd title after beating Rangers 3–3 (5-4 pen.) at Hampden Park on 15 December 2024.

The domestic television rights are held by Premier Sports who replaced BT Sport from the 2019–20 season.

Historically, the Scottish League Cup has oscillated between being a straightforward single-elimination knockout tournament and having an initial group phase. Since the 2016–17 season, the League Cup has used a group phase format. The format has eight groups of five teams playing each other once in a round-robin format. The forty teams playing in the group stage consist of the 38 league clubs who are not participating in UEFA competitions, along with two teams from outside the league. In the group phase, three points are given for a win and one point for a draw. If matches are level after ninety minutes, a penalty shoot-out is held with the winning team gaining a bonus point. The groups are regionalised: there are four groups in the North section, and four in the South section, with three pots for each regional section – top seeds, second seeds, and unseeded clubs. Each group will consist of one top seed, one second seed, and three unseeded clubs.

The eight group winners and three best runners-up progress into the second round, where they are joined by the five clubs participating in UEFA competitions. The tournament then adopts a single-elimination knockout format. There are no replays, which means all drawn matches are decided by extra time and a penalty shootout, if necessary. The semi-final matches are played on a neutral ground, determined by the location and size of supports involved. The final game is traditionally played at Hampden Park in Glasgow, though due to renovations some finals have been played at other venues, such as Celtic Park or Ibrox Stadium. The new format also allowed the SPFL to reintroduce the two-weekend winter break in January. Along with the newly designed tournament, a new television deal for it was announced as BT Sport took over rights from BBC Scotland. In February 2016 the SPFL announced the League Cup final would be moved to November.

The cup has its origins in a regional cup competition called the Southern League Cup which was introduced in 1940 when wartime restrictions led to a suspension of the Scottish Cup. This tournament did not involve all of the teams who comprised the Scottish Football League prior to the outbreak of war, although its last, expanded edition after the conflict ended was well-attended, demonstrating enthusiasm amongst supporters for the continuation of such a tournament. The first official Scottish Football League Cup was contested during the 1946–47 season, when Rangers defeated Aberdeen in the final.

The competition was very popular with supporters during the first few decades of its existence. The tournament consisted of 8 or 9 groups consisting of 4 or 5 teams. The groups were seeded into two sets with the top 16 teams in Division One making up the first four groups, guaranteeing that four 'big' teams would play four 'lesser' teams in the quarter-finals. From 1949–50 to 1998–99 the final was played prior to the festive season which provided the excitement of an early trophy on offer, except in 1968–69 (postponed due to a fire at Hampden), 1977–78, 1978–79 and 1983–84 (an experimental season with a group stage in the third round followed by the semi-finals).

Extra league fixtures after the Scottish Premier Division was formed in 1975 and expanding European competitions meant that by the early 1980s the League Cup's long-winded format, which involved group rounds played early in the season leading to two-legged knock-out rounds, attracted much criticism. From 1984–85 the tournament was revamped to a shorter, single elimination knock-out format. From that period Rangers became the dominant force in the competition having previously been roughly level with Celtic in terms of trophies, winning nine times in twelve years to increase their total to 20 before Celtic won their tenth in 1997–98.