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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1. 2017-18: Christian Walton - Brighton to Wigan (loan)
Although Walton technically signed for Wigan in the summer of 2017, that particular deal was only a short-term deal which was extended twice - with the latter in the winter. The Seagulls stopper played an integral part in the Latics promotion and FA Cup run that saw him keep a clean sheet in a historic 1-0 win over Manchester City. (Photo by Alex Livesey/Getty Images) Photo: Alex Livesey
2. 2017-18: Michael Smith (Bury to Rotherham United)
After underwhelming spells at Pompey, Northampton and Bury, Rotherham took a chance on Smith and it's punt that's paying off. The 30-year-old has scored 17 goals in all competitions this term with the Millers at the League One summit. (Photo by George Wood/Getty Images) Photo: George Wood
3. 2018-19: Cauley Woodrow (Fulham to Barnsley)
After impressing on-loan for Barnsley, the Yorkshire club made Woodrow's stay permanent in January 2019. The former Fulham man spearheaded the cub's charge to the Championship at the end of the same season and also played a sizable part in Tykes top-six Championship finish last term. (Photo by Alex Livesey/Getty Images) Photo: Alex Livesey
4. 2018-19: Jonny Williams (Crystal Palace to Charlton Athletic)
The arrival of Williams at Charlton strengthened the club's play-off credentials further. And the former Eagles academy product helped the Addicks to a dramatic 2-1 play-off final victory over Sunderland at the end of the season. (Photo by George Wood/Getty Images) Photo: George Wood