15 January ~ The new national third division comprised 21 clubs from the Southern League plus Grimsby who had finished bottom of Division Two in 1919-20. At the end of this season, another 20 clubs joined and the third level was split into two sections, North and South. The League kept this structure until the creation of Division Four in 1958-59.
Crystal Palace went top through their win at Millwall and remained there for the rest of the season, taking the title by five points from Southampton. Their Scottish striker Jack Conner scored the only goal at The Den and went on to be the division's top scorer with 29 goals. Millwall were to be the division’s best supported club with an average of 18,160, which was better than three clubs in Division One. Exeter City got the lowest gates but still averaged a respectable 7,050.
Only the champions were promoted, with the one-up system retained when the division was regionalised. Plymouth, runners up to Southampton in Division Three South in 1921-22, finished second for six successive seasons; they finally won promotion in 1929-30.
One of Brentford's goals in their win at Gillingham was scored by Irish striker Reg Boyne, a new signing from Loughborough Brush Works who was playing his only League season. Gillingham finished bottom with Brentford directly above them but both clubs were allowed to keep their places without being put up for re-election.
Merthyr Town were League members until being voted out at the end of 1929-30. They went out of business four years later. Their successor club, Merthyr Tydfil, formed in 1945, and reverted to the Merthyr Town name after another bankruptcy in 2010. They are one of three Welsh clubs currently in the English non-League system, along with Wrexham and Colwyn Bay.
Among the distinctive names playing this season were: Zilwood March (Brighton), Bertie Menlove (Bristol Rovers), Tommy Talks (Grimsby), Prince Blott (Newport) and Billy Tout (Swindon).