The January 2022 transfer window in the UK commenced on Saturday the 1st January 2022 and concluded on Monday the 31st January 2022.The final hour of the window saw moves for midfielders Jeff Hendrick and Jamie McGrath, two current internationals. Hendrick joins QPR on loan to the end of the season while McGrath has joined Wigan Athletic on a two year contract for an undisclosed fee. Throughout the window, there was some significant Irish activity, predominantly involving players from and to the Airtricity League. On the Irish domestic scene, the return of Jack Byrne from Cypriot club APOEL Nicosia to Shamrock Rovers and that of Eoin Doyle from Bolton Wanderers to St Patrick’s Athletic on a three year contract have been the highlights. The journey East to the UK has been made by a number of players with Ross Tierney and Georgie Kelly from Bohemian to Motherwell and Rotherham United respectively and the Sligo Rovers duo of Johnny Kenny to Glasgow Celtic and John Mahon to St Johnstone being the highest profile. Senior international striker Aaron Connolly has made a loan move from Brighton & Hove Albion to Championship side Middlesbrough while Cyrus Christie has moved on loan from Fulham to Swansea City.
| Name | From | To | Details |
| James Abankwah | St Patrick’s Ath | Udinese (Italy) | €500,000 |
| James Brown | Drogheda United | Blackburn Rovers | 6mth deal |
| Jack Byrne | APOEL Nicosia | Shamrock Rovers | Undisclosed |
| Killian Cahill | Shamrock Rovers | Brighton & Hove | Undisclosed |
| Niall Canavan | Bradford City | Barrow | Undisclosed |
| Harry Charsley | Mansfield Town | Port Vale | Undisclosed |
| Cyrus Christie | Fulham | Swansea City | EoS Loan |
| Daniel Cleary | Dundalk | St Johnstone | Free EoC |
| Aaron Connolly | Brighton & Hove | Middlesbrough | EoS Loan |
| Dylan Connolly | Northampton Town | Morecambe | 18 mths |
| Rob Cornwall | Bohemian | North Colorado | EoC |
| Conor Coventry | West Ham United | MK Dons | EoS Loan |
| Ryan Delaney | Morecambe | Scunthorpe Utd | EoS Loan |
| Lee Desmond | St Patrick’s Ath | Sacramento Rep | EoC |
| Jamie Devitt | Barrow | Carlisle United | Undisclosed |
| Eoin Doyle | Bolton Wanderers | St Patrick’s Ath | 3Yr Deal |
| Cathal Heffernan | Cork City | AC Milan | Loan + |
| Jeff Hendrick | Newcastle United | QPR | EoS Loan |
| Callum Kavanagh | Middlesbrough | Harrogate Town | EoS Loan |
| Georgie Kelly | Bohemian | Rotherham United | 3Yr Deal |
| Johnny Kenny | Sligo Rovers | Glasgow Celtic | €150,000 |
| John Mahon | Sligo Rovers | St Johnstone | Undisclosed |
| Conor Masterson | QPR | Gillingham | EoS Loan |
| Jamie McGrath | St Mirren | Wigan Athletic | Undisclosed |
| Ademipo Odubeko | West Ham United | Doncaster Rovers | EoS Loan |
| Aiden O’Brien | Sunderland | Portsmouth | EoS Deal |
| Jake O’Brien | Crystal Palace | Swindon Town | EoS Loan |
| Lee O’Connor | Glasgow Celtic | Tranmere Rovers | Undisclosed |
| Thomas O’Connor | Burton Albion | Wrexham | Undisclosed |
| Kieran O’Hara | Burton Albion | Fleetwood Town | EoS Deal |
| Corey O’Keefe | Mansfield Town | Rochdale | EoS Deal |
| Daniel O’Reilly | Drogheda United | Hamilton Accies | Free EoC |
| Killian Phillips | Drogheda United | Crystal Palace | £50,000 |
| Christy Pym | Peterborough Utd | Stevenage | EoS Loan |
| Glen Rea | Luton Town | Wigan Athletic | EoS Loan |
| Ali Reghba | Leicester City | CR Belouizdad | Undisclosed |
| Lewis Richards | Wolverhampton W | Harrogate Town | EoS Loan |
| Kieran Sadlier | Rotherham United | Bolton Wanderers | 2Yr Deal |
| Deji Sotona | Nice | Brentford | Undisclosed |
| Ross Tierney | Bohemian | Motherwell | Free EoC |
| Tyreik Wright | Aston Villa | Colchester Utd | EoS Loan |