All three clubs have fairly recent memories of the Championship, as well as strong fanbases and talented squads. However, the third tier is notoriously difficult to escape.
That is something Barnsley can attest to, having suffered play-off heartbreak at the end of the last two campaigns. Huddersfield and Rotherham, meanwhile, tumbled out of the Championship last term.
What makes League One harder is the amount of money now being thrown around the division. Wrexham and Stockport County are newcomers in League One but spent the summer flexing their financial muscles, building enviable squads.
Birmingham City have also invested heavily and shocked the country when they smashed the League One transfer record to sign Jay Stansfield from Fulham. The forward joined the Blues for a reported £15m.
But which League One squad is the most valuable? Here are the most expensive squads in the division, according to Transfermarkt data.
1. League One's most expensive squads
Every squad in League One - ranked from the least expensive to the most. Photo: Catherine Ivill/Getty Images
