The window, open until November 24th, allows clubs to sign players for a maximum of 93 days. Any extension of the deal has to be done upon the initial deal expiring.
A host of Barclays Premier League players who have been left out of their teams' 25-man squad for the new season are those most likely to seek a move away.
GiveMeFootball.com profiles five players who are most likely to crave such a move.
Wayne Bridge - Manchester City
The wage demands of many of City's first-team peripherals has only gone to stall many of their exits, with Bridge unable to force a move through before the end of the transfer window. However, the loan window could work as a reprieve for the 31-year-old, who spent part of last season on loan at West Ham United.
Josh McEachran - Chelsea
One of the hottest young prospects in English football was expected to be given more first-team opportunities this season after Andre Villas-Boas revealed he had turned down a loan offer for the England Under-21 international. However, the signings of Raul Meireles and Juan Mata may further restrict his involvement, and The Blues could look to the success of Tom Cleverley and Jack Wilshere's loan spells and their subsequent emergence as a good indicator to allow McEachran to depart.
Giovani dos Santos - Tottenham Hotspur
With the likes of Gareth Bale, Aaron Lennon and Rafael van der Vaart in the Spurs ranks, Harry Redknapp perceives it difficult to provide the Mexican with regular first-team opportunities. His staring role in the Gold Cup earlier in the summer proved he's got what it takes to shine, but four goals in eight games during a loan spell at Ipswich Town could tempt many in the lower echelons.
Danny Wilson - Liverpool
Brought for £2 million, Wilson was immediately thrust from the Rangers first-team to Liverpool reserves, which initially put the breaks on the Scot's emergence. His first Barclays Premier League start came seven months later, one of only two he made in the league all season. The signings of Jose Enrique and Sebastian Coates won't improve his chances either, and he's already intimated he needs a loan move to maintain his international place.
Federico Macheda - Manchester United
The Italian may have burst on the scene in emphatic fashion in 2008 with his curling effort against Aston Villa, but since Sir Alex Ferguson's acquisition of Javier Hernandez and retention of Dimitar Berbatov, Macheda's Old Trafford career has wavered. Linked with Newcastle United in the summer, Danny Welbeck's emergence should consign him to another season away from the 19-time English League champions.