Marlon Pack became Pompey’s first acquisition of the summer, returning on a free deal from Cardiff.
The 31-year-old was soon followed by the arrivals of Zak Swanson, Joe Rafferty, Josh Griffiths, Joe Pigott and Josh Oluwayemi before Colby Bishop became the latest name to join the ranks after joining for an undisclosed fee from Accrington.
In total, seven fresh faces have arrived through the door at Fratton Park, while Marcus Harness remains the only name to depart.
But how does the Blues’ summer transfer business compare to their League One rivals?
We’ve taken a look at the most – and least – active clubs in the third tier so far this window.
Here’s what we discovered.
5. Cambridge
Number of signings: 4; Signings: Brandon Haunstrup (Kilmarnock - free), James Holden (Reading - free), Zeno Ibsen Rossi (Bournemouth - undisclosed), Saikou Janneh (Bristol City - undisclosed). Photo: Alex Pantling
6. Bolton
Number of signings: 4; Signings: Jack Iredale (Cambridge - free), James Trafford (Manchester City - loan), Eoin Toal (Derry - undisclosed), Connor Bradley (Liverpool - loan). Photo: Jacques Feeney
7. Bristol Rovers
Number of signings: 4; Signings: John Marquis (Lincoln - free), James Gibbons (Port Vale - free), Jordan Rossiter (Fleetwood - undisclosed), James Connolly (Cardiff - undisclosed). Photo: Jason Brown
8. Ipswich
Number of signings: 5; Signings: Marcus Harness (Pompey - undisclosed), Freddie Ladapo (Rotherham - free), Greg Leigh (Morecambe - free), Dom Ball (QPR - free), Tyreece John-Jules (Arsenal - loan). Photo: Jason Brown