A UEFA Champions League club may register a maximum of three new eligible players for the remaining matches by 24:00 CET on 1 February (the transfer deadlines themselves are set by individual national associations) The full procedures around player registration can be found in Article 44 of the official competition regulations.
Club by club
Barcelona
In: Philippe Coutinho (Liverpool), Yerry Mina (Palmeiras)
Out: Arda Turan (İstanbul Başakşehir, loan), Rafinha (Internazionale Milano, loan), Javier Mascherano (Hebei China Fortune), Gerard Deulofeu (Watford, loan)
Basel
In: Fabian Frei (Mainz), Samuele Campo (Lausanne), Valentin Stocker (Hertha Berlin)
Out: Alexander Fransson (Lausanne, loan), Renato Steffen (Wolfsburg), Manuel Akanji (Borussia Dortmund), Cédric Itten (St Gallen)
Bayern München
In: Sandro Wagner (Hoffenheim)
Out: Marco Friedl (Werder Bremen, loan)
Beşiktaş
In: Domagoj Vida (Dynamo Kyiv), Vágner Love (Alanyaspor)
Out: Cenk Tosun (Everton), Orkan Çınar (Konyaspor, loan), Matej Mitrović (Club Brugge, loan)
Chelsea
In: Ross Barkley (Everton)
Out: Diego Costa (Atlético Madrid), Jake Clarke-Salter (Sunderland, loan), Kenedy (Newcastle, loan)
Juventus
In: none
Out: Marko Pjaca (Schalke, loan), Nicola Leali (Perugia, loan)
Liverpool
In: Virgil van Dijk (Southampton), Ryan Kent (Freiburg, end of loan)
Out: Philippe Coutinho (Barcelona), Marko Grujić (Cardiff City, loan), Corey Whelan (Yeovil Town, loan), Matty Virtue (Notts County, loan), Cameron Brannagan (Oxford United)
Manchester City
In: Aymeric Laporte (Athletic)
Out: Shay Facey (Northampton Town), Isaac Buckley (Oxford United, loan), Marlos Moreno (Flamengo, loan), Kean Bryan (Oldham Athletic, loan)
Manchester United
In: Alexis Sánchez (Arsenal), Cameron Borthwick-Jackson (Leeds Unied, recall from loan)
Out: James Wilson (Sheffield United, loan), Henrikh Mkhitaryan (Arsenal), Alex Tuanzebe (Aston Villa, loan)
Paris Saint-Germain
In: Lassana Diarra (Free agent)
Out: Romain Habran (Royal Antwerp), Rémy Descamps (Tours, loan)
Porto
In: Majeed Waris (Lorient, loan), Paulinho (Portimonense, loan)
Out: João Costa (Gil Vicente, loan), Miguel Layún (Sevilla, loan)
Real Madrid
In: none
Out: none
Roma
In: none
Out: Leandro Castan (Cagliari, loan), Edoardo Soleri (Almería, loan), Arturo Calabresi (Foggia, loan), Umar Sadiq (NAC Breda, loan)
Sevilla
In: Guilherme Arana (Corinthians), Miguel Layún (Porto, loan), Roque Mesa (Swansea, loan)
Out: Walter Montoya (Cruz Azul), Borja Lasso (Osasuna, loan), Michael Krohn-Dehli (Deportivo La Coruña)
Shakhtar Donetsk
In: Dodô (Curitiba)
Out: Marcio Azevedo (PAOK, loan)
Tottenham Hotspur
In: none
Out: Georges-Kévin N’Koudou (Burnley, loan), Cameron Carter-Vickers (Ipswich Town, loan), Marcus Edwards (Norwich City, loan), Ryan Loft (Exteter City, loan)
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