Preston North End spent £1.046m on agents fees between February 2017 and January this year.
Sixteen clubs in the Championship paid football's middle-men more than PNE did, Aston Villa the top spenders with more than £5.5m going to agents.
Sunderland spent the second highest highest amount - £4.3m - while Reading's £2.8m was the third highest spend.
The seven Championship clubs to spend less on agents than North End were Barnsley, Bolton, Bristol City, Burton, Ipswich, Millwall and Sheffield United.
More than £42m was spent in total in the Championship on agents fees.
PNE's agent payments covered 17 transactions between February 1 last year and January 31 this year.
Those transactions including incoming transfers, new contracts and one contract cancellation - that of Liam Grimshaw.
The figures were released by the Football Association on Tuesday evening.
In the Premier League, Liverpool were the highest spenders when it came to agents, paying £26.7m.
Chelsea paid out £25.1m, Manchester City £23.4m and Manchester United £18m.
All 92 clubs in the Premier League and EFL paid agent fees of varying degrees, Crawley Town in League Two spending the least amount - £4,680.