The market saw the Blues sign impressive youngsters Ryley Towler and Paddy Lane for undisclosed fees from Bristol City and Fleetwood respectively.
Meanwhile, defender Di’Shon Bernard and Matt Macey arrived on loan deals for the remainder of the campaign from Manchester United & Luton respectively.
Indeed, three of Pompey’s first-team regulars saw the exit in January, with Josh Koroma and Josh Griffiths ending their season-long loan stays prematurely, while Michael Morrison joined Cambridge on a permanent deal.
But how does the Blues’ squad values compare to their League One rivals?
We’ve taken a look at Transfermarkt’s estimated figures to see which club they believe have the highest-priced squad in the third tier following the closure of the window.
Here’s what we discovered.