Premier League clubs may have tight schedules with games coming thick and fast this season but that doesn't mean they will take their eye off the January transfer window.
In fact, business during January could be more important than ever as teams look to juggle their squads to give key players rest and hope their strength in depth can help cover.
So keep up to date with all the latest ins and outs as Sportsmail details the list of all the key Premier League transfers of players to have at least made a senior appearance.
Arsenal
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NONE
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Matt Macey (Hibernian, free)
William Saliba (Nice, loan)
Sead Kolasinac (Schalke, loan)
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Aston Villa
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NONE
OUT
Lovre Kalinic (Hajduk Split, loan)
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Brighton
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NONE
OUT
Jayson Molumby, (Preston North End, loan)
Viktor Gyokeres (Coventry City, loan)
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Burnley
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NONE
OUT
NONE
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Chelsea
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NONE
OUT
Lucas Piazon (Braga, undisclosed)
Charlie Brown (MK Dons, undisclosed)
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Crystal Palace
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NONE
OUT
Max Meyer (released)
Jaroslaw Jach (Rakow, loan)
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Everton
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NONE
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Jarrad Branthwaite (Blackburn Rovers, loan)
Matthew Pennington (Shrewsbury Town, loan)
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Fulham
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NONE
OUT
NONE
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Leeds United
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NONE
OUT
Jordan Stevens (Bradford City, loan)
Robbie Gotts, (Salford City, loan)
Ryan Edmondson (Northampton Town, loan)
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Leicester
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NONE
OUT
Islam Slimani (Lyon, free)
Matty James (Coventry City, loan)
Filip Benkovic (Leuven, loan)
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Liverpool
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NONE
OUT
Adam Lewis (Plymouth Argyle, loan)
Liam Millar (Charlton Athletic, loan)
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Manchester City
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Filip Stevanovic (Partizan Belgrade, £6m)
OUT
Filip Stevanovic (Partizan Belgrade, loan)
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Manchester United
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Amad Diallo (Atalanta, £37m)
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Timothy Fosu-Mensah (Bayer Leverkusen, £1.