The period can be notoriously difficult to operate in with teams unwilling to sell their prized assets and demand high.
There will be a number of high-profile deals clubs in the third tier may want to replicate or avoid at all costs.
Click through the list of some of the best and worst League One transfers in recent history.
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13. 2018-19: Will Grigg (Wigan to Sunderland)
Perhaps the most damning deal on the list. Sunderland signed the former Wigan man for almost £4million to gift them an immediate return to the Championship which is still yet to come. He's scored eight goals for the Black Cats and has since been loaned to MK Dons and Rotherham (Photo by Harriet Lander/Getty Images) Photo: Harriet Lander
14. 2018-19: Lloyd Isgrove (Barnsley to Pompey) - loan
Isgrove is a member of the fateful Pompey January signings of 2019. The now Bolton man never played in royal blue and featured on the bench only three times. (Photo by Naomi Baker/Getty Images) Photo: Naomi Baker
15. 2018-19: Jonte Smith (Lewes to Oxford United)
After scoring goals for non-league Lewes, the U's took a risk on his ability in the EFL. However the gamble didn't play off as he played once for the club before spells at Cheltenham, Woking, and now Ballymena in Northern Ireland. (Photo by Marc Atkins/Getty Images) Photo: Marc Atkins
16. 2019-20: Jacob Mellis (Mansfield to Bolton)
Couldn't prevent Bolton from sliding out of League One into the fourth tier. (Photo by James Chance/Getty Images) Photo: James Chance