But which teams made the best - and worst - use of the 31-day opportunity to fill holes and fix problems in their squad?
NU-Mad looks at the winners and losers of the transfer window from teams chasing Europe or looking to avoid the drop.
WINNERS
Chelsea
It was a very busy January transfer window for Jose Mourinho and Chelsea.
The club said goodbye to fans favourite Juan Mata but with the arrival of Nemanja Matic, Mohamed Salah, Bertrand Traore and Kurt Zouma, we got a glimpse of what the future may hold at Stamford Bridge under the Portuguese.
Mourinho would love to win the Champions League with Chelsea and by signing some of Europe's most exciting young players it looks like he thinks that is the best way of doing it.
The London club may not pip City to the title this season, despite their 1-0 win at the Etihad Stadium, but by signing such players in January it's clear Mourinho plans on building a side that will be successful at home and abroad for many years.
The former Inter Milan manager returned to the club in the summer and you wouldn't bet against some of his latest additions helping him achieve greater success in the near future.
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Crystal Palace
Who would have thought that Crystal Palace would be in this position when Ian Holloway left the club in October?
Granted, Tony Pulis's style of play might not suit everyone but Palace now have a genuine chance of staying in the Premier League.
And what better way of rewarding your fans and tiring squad than introducing a few new faces during the January window. The Palace board gave Pulis plenty of backing by sanctioning a quintet of deals to bolster their attempts to avoid relegation.
England Under-21 international Tom Ince was the pick of the bunch but he was well supported by the arrival of Joe Ledley, Wayne Hennessey, Scott Dann and Jason Puncheon (on a permanent basis).
The south London club are far from safe but if the new signings can provide a boost in the same way as Pulis did when he arrived then Palace will be able to prepare for another year in the Premier League.
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LOSERS
Arsenal
Arsenal's impressive start to the season could be about to hit a brick wall. The north London club currently sit top of the Premier League but Arsene Wenger's failure to secure a striker instead of an unfit midfielder in the January transfer window could cost the club points and more importantly a trophy.
Alex Oxlade-Chamberlain has returned to action injury free and in good goal scoring form but with a further five games left in February alone, French striker Olivier Giroud is going to have to be at his goal scoring best on a pretty regular basis if Arsenal's pursuit of domestic and European honours is to continue.
With that in mind, Friday's loan chase of Spartak Moscow's Kim Kallstrom appears all the more bizarre, especially as since his Arsenal medical, Kallstrom has been ruled out for at least a month with a back issue.
Don't worry though Arsenal fans, because Wenger wasn't completely convinced about his new arrival anyway. The Arsenal boss has since admitted that he would not have sanctioned the loan signing if there was more time to find an alternative player.
Arsenal to miss out on a trophy for another season? You wouldn't bet against it.
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Manchester United
United's 2-1 defeat at Stoke highlighted exactly why January was such a poor month for David Moyes in the transfer market.
The exceptionally talented Juan Mata was purchased from one time rivals Chelsea and will provide a further threat going forward next to the likes of Robin Van Persie and Wayne Rooney.
But, Moyes' men have real trouble in the centre of the park and when Michael Carrick was asked to play in defence after Phil Jones and Jonny Evans picked up injuries, Tom Cleverley once again failed to impress.
Sir Alex Ferguson had the ability to take an average squad and somehow get it to challenge for silverware. Moyes isn't blessed with the same magic touch and because he failed to address United's real issue, the centre of the park, Cleverley et al look certain to miss out on fourth spot this season.
No Champions League football at Old Trafford next season?
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Newcastle
Will he go? Will he stay? In the end, and some might say inevitably, Yohan Cabaye joined a club that could offer him Champions League football.
And as the French international made his way to Paris Saint-Germain, the Newcastle faithful let owner Mike Ashley know their feelings on his departure during the 3-0 defeat to great rivals Sunderland.
If the club needed a warning of what was about to happen then they only needed to look back to August when Cabaye refused to play for Pardew's side following the reported interest from Arsenal.
If and probably when Newcastle fail to reach their targets for the season they only have themselves to blame. Cabaye is hard to replace but Newcastle have a better chance of playing European football next season with him than without him.
The French playmaker wanted out for several months but that means the club had several months to find a suitable replacement.