The 1955/56 season was the 83rd season of competitive football in Scotland and the 59th season of the Scottish Football League.
Following league reconstruction League Division One was expanded from 16 to 18 teams.
League Division Two was expanded from 16 to 19 teams with Berwick Rangers, Dumbarton, East Stirlingshire, Montrose and Stranraer joining the league.
The leagues were rebranded at the start of season 1955-56. Division A was now the newly named Division One and Division B was now the newly named Division Two.
New manager Neil Mc Bain made the difference between a mid-league position and the second place which gained United promotion to the 1st division.
United had opened with eight wins out of ten. Wins over Dumbarton (5-1), East Stirling (8-1) and St Johnstone (4-3) helped Ayr to 27 points by the year end. Other highlights were a 7-0 over Montrose and 8-1 over Forfar Athletic and an Easter Saturday 4-0 win against East Stirling.
A 5-0 win over Arbroath and a 0-0 draw at Perth left Ayr 46 points from 32 games. 15,000 people saw United win 2-0 against Brechin City and achieve promotion.