Fulham and Brentford both appear twice in a list of the top 15 most expensive deals in the history of the Championship, according to football365.
These figures are based on initial fees only, and exclude any potential future fees.
The list was compiled after Wolves completed the signing of Ruben Neves for £15.8m.
This toppled the previous record set by Wolves in January, when they completed the permanent deal for Helder Costa.
Fulham occupy joint-third and fifth spot in the table, for the sale and purchase of striker Ross McCormack who left for £12m and was brought to Craven Cottage for £11m.
Brentford's two most expensive deals sit in joint ninth in the table, with the sales of Scott Hogan to Aston Villa, and Andre Gray to Burnley, sitting on Par with Jordan Rhodes' move from Blackburn to Middlesbrough for the sum of £9m.
Other notable fees include Matt Ritchie's move from Bournemouth to Newcastle (£12m) which sits in joint-third with McCormack's sale to Villa, Jonathan Kodjia's move from Bristol City to Aston Villa (£11m) and Dwight Gale's move from Crystal Palace to Newcastle (£10m) which sits in seventh place.