Huddersfield and Fulham were relegated from the Premier League last season, along with Cardiff City, but start the new campaign with contrasting fixtures.
Beaten play-off finalist Derby - managed by Frank Lampard, the favourite for the Chelsea job - goes to Huddersfield to conclude the opening round of fixtures on 6 August (local time).
Jan Siewert's side faces a particularly tough start, with Fulham and Cardiff also on the agenda in its first four matches.
The season starts on 3 August with League One winner Luton Town hosting Middlesbrough, while Charlton Athletic travels to Blackburn Rovers and Cardiff visits Wigan Athletic the next day.
The regular season will end on 3 May, with Leeds United against Charlton perhaps the pick of the final-day fixtures.
The 'spygate' saga from 2018-2019 saw Leeds and Derby forge a rivalry that included a play-off semi-final win for Lampard's men, and they play at Elland Road on 22 September, before a crunch clash at Pride Park on the penultimate weekend.
Cardiff's relegation means a reprisal of the South Wales derby with Swansea City on 27 October and 12 January.
Luton host Fulham on Boxing Day, while West Brom - also beaten play-off semi-finalists - entertain Leeds on New Year's Day.