Lee Johnson has added Carl Winchester, Jordan Jones, Jake Vokins and Ross Stewart to his roster over the course of the last month and will hope the quarter can help drive the Black Cats up the table in the coming weeks.
But where do the experts think Sunderland will finish after their transfer business, and who are they tipping for promotion to the Championship?
The data analysts at FiveThirtyEight have released their latest predictions on how the League One table will finish - and it makes for interesting reading after a January transfer window that has seen some clubs far busier than others.
So scroll down and click through the pages as we see where their unique formula is predicting Johnson’s men to finish come the end of the 2020/21 campaign:
1. 24th - Burton Albion
The Brewers currently sit bottom of League One and have had a busy January as they look to claw themselves away from danger - but the experts don't think that will be enough to stave off relegation. Predicted points total: 38 Photo: Nathan Stirk
2. 23rd - AFC Wimbledon
Comfortably beaten by Sunderland last month, the Dons have just dismissed manager Glyn Hodges as they look to climb away from relegation danger. The experts aren't too confident that will happen, though. Predicted points total: 42 Photo: Justin Setterfield
3. 22nd - Swindon Town
The Robins currently sit in the bottom four, and aren't being tipped to escape the relegation zone before the season comes to a close. Predicted points total: 44 Photo: Alex Davidson
4. 21st - Northampton Town
They may have held Sunderland to a draw earlier this year, but the experts don't think the Cobblers will be able to keep their heads above water and secure a second season in League One. Predicted points total: 45 Photo: Pete Norton