The Championship club have brought in Charlotte midfielder Riley McGree, Brighton & Hove Albion’s Aaron Connolly and Arsenal’s Folarin Balogun.
Neil Taylor also agreed a contract extension with the club after joining on a short-term contract in November.
Dejan Stojanovic has joined FC Ingolstadt on loan until the end of the season, while Middlesbrough are facing a challenge to keep hold of Djed Spence before the deadline.
The full-back is enjoying a brilliant loan spell with Nottingham Forest and has attracted the attention of a number of clubs including Arsenal and Tottenham Hotspur.
Here are the best of today’s transfer deadline day rumours...
1. Barnsley eye Man City full-back
Barnsley are targeting a move for Manchester City's Luke Bolton before tonight's deadline. The 22-year-old has spent the last three seasons on loan with Wycombe Wanderers, Luton Town and Dundee United. (Football Insider) Photo: Manchester City FC
2. Oxford United targeting Luton striker
Oxford United are lining up a return for former striker Danny Hylton, who joined Luton Town from the Us in 2016. The 32-year-old has only made five Championship appearances this season. (Football League World) Photo: James Gill - Danehouse
3. Terriers to sign second Chelsea loanee
Huddersfield Town are reportedly poised to seal a loan move for Chelsea's Tino Anjorin, joining Levi Colwill at the John Smith's Stadium. Southampton have also been linked with the midfielder. (Football League World) Photo: Paolo Bruno
4. Bournemouth agree fee for Posh starlet
Bournemouth have reportedly agreed a fee with Peterborough United for Siriki Dembele. The winger previously rejected a move to Birmingham City after Posh accepted a £1.5 million bid from the Blues. (Bournemouth Echo) Photo: Julian Finney