| 2026-10-14 | T. Adeyemo | Watford → Barnsley | Free agent |
| 2026-10-08 | Leo Farrell | Barnsley → Altrincham | Loan |
| 2026-09-14 | J. Okedina | Bohemians → Barnsley | Free agent |
| 2026-09-06 | Georgie Gent | Barnsley → Boston United | Loan |
| 2026-08-31 | K. Nwakali | Barnsley → Omonia Nicosia | Free agent |
| 2026-08-31 | K. Nwakali | Barnsley → Omonia 29is Maiou | Free agent |
| 2026-08-31 | C. O'Keeffe | Barnsley → Bradford | Transfer |
| 2026-08-30 | K. Nwakali | Barnsley → Omonia 29is Maiou | Free agent |
| 2026-08-30 | C. O'Keeffe | Barnsley → Bradford | Transfer |
| 2026-08-29 | B. Touré | Annecy → Barnsley | Free agent |
| 2026-08-28 | B. Touré | Annecy → Barnsley | Free agent |
| 2026-08-28 | Z. Larkeche | QPR → Barnsley | Loan |
| 2026-08-26 | C. O'Riordan | Blackburn → Barnsley | Loan |
| 2026-08-25 | J. Earl | Barnsley → Blackpool | Transfer |
| 2026-08-24 | J. Earl | Barnsley → Blackpool | Transfer |
| 2026-08-24 | K. Łopata | Barnsley → Lechia Gdansk | Transfer |
| 2026-08-23 | K. Łopata | Barnsley → Lechia Gdansk | Transfer |
| 2026-08-17 | M. de Gevigney | Barnsley → Silkeborg | Transfer |
| 2026-08-16 | M. de Gevigney | Barnsley → Silkeborg | Transfer |
| 2026-08-04 | C. Lennon | Barnsley → Yeovil Town | Loan |
| 2026-07-30 | S. Gale | Gillingham → Barnsley | Transfer |
| 2026-07-29 | S. Gale | Gillingham → Barnsley | Transfer |
| 2026-07-15 | M. Watters | Barnsley → Port Vale | Free agent |
| 2026-07-15 | M. Kirk | Portsmouth → Barnsley | Loan |
| 2026-07-14 | A. Richards | Leicester → Barnsley | Transfer |
| 2026-07-13 | T. Noslin | Telstar → Barnsley | Transfer |
| 2026-07-12 | T. Noslin | Telstar → Barnsley | Transfer |
| 2026-07-12 | C. Slicker | Ipswich → Barnsley | Loan |
| 2026-07-01 | C. Taylor | Newcastle Jets → Barnsley | Free agent |
| 2026-07-01 | Isaac Smith | Manchester City → Barnsley | Transfer |
| 2026-06-30 | A. Phillips | Barnsley → Bradford | Transfer |
| 2026-06-30 | J. Russell | Barnsley → Mansfield Town | Free agent |
| 2026-06-30 | J. Smith | Barnsley → Port Vale | Transfer |
| 2026-06-30 | A. Dallas | Barnsley → Walsall | Free agent |
| 2026-06-30 | C. McGeehan | Northampton → Barnsley | Free agent |
| 2026-06-30 | E. O'Connell | Barnsley → Stockport County | Free agent |
| 2026-06-30 | D. McGoldrick | Barnsley → Mansfield Town | Free agent |
| 2026-06-30 | Rogan Ravenhill | Matlock Town → Barnsley | - |
| 2026-06-30 | R. Brownlie | Brisbane Roar → Barnsley | Free agent |
| 2026-06-30 | Aston Wilson | Barnsley → Oldham | Free agent |
| 2026-06-29 | M. Watters | Barnsley → Watters Max | Free agent |
| 2026-06-29 | M. Watters | Dundee Utd → Barnsley | Return from loan |
| 2026-06-29 | M. Watters | Barnsley → Port Vale | Free agent |
| 2026-06-29 | A. Phillips | Barnsley → Bradford | Transfer |
| 2026-06-29 | J. Russell | Barnsley → Mansfield Town | Free agent |
| 2026-06-29 | M. Roberts | Barnsley → Roberts Marc | Free agent |
| 2026-06-29 | J. Smith | Barnsley → Port Vale | Transfer |
| 2026-06-29 | J. Smith | Grimsby → Barnsley | Return from loan |
| 2026-06-29 | A. Dallas | Southend → Barnsley | Return from loan |
| 2026-06-29 | A. Dallas | Barnsley → Walsall | Free agent |
| 2026-06-29 | C. McGeehan | Northampton → Barnsley | Free agent |
| 2026-06-29 | K. Łopata | Walsall → Barnsley | Return from loan |
| 2026-06-29 | T. Watson | Barnsley → Watson Tennai | Free agent |
| 2026-06-29 | Fábio Jaló | Oldham → Barnsley | Return from loan |
| 2026-06-29 | O. Goodman | Barnsley → Crystal Palace | Return from loan |
| 2026-06-29 | S. Banks | Barnsley → FC St. Pauli | Return from loan |
| 2026-06-29 | J. Okedina | Bohemians → Barnsley | Free agent |
| 2026-06-29 | C. Taylor | Newcastle Jets → Barnsley | Free agent |
| 2026-06-29 | Aston Wilson | Barnsley → Oldham | Free agent |
| 2026-05-30 | J. Russell | Mansfield Town → Barnsley | Return from loan |
| 2026-05-30 | T. Bradshaw | Barnsley → Oxford United | Return from loan |
| 2026-05-30 | N. Ogbeta | Barnsley → Plymouth | Return from loan |
| 2026-05-30 | T. Chirewa | Barnsley → Wolves | Return from loan |
| 2026-05-30 | Xu Bin | Barnsley → Wolves | Return from loan |
| 2026-04-03 | S. Flinders | Barnsley → Flinders Scott | Free agent |
| 2026-04-01 | S. Flinders | Mansfield Town → Barnsley | - |
| 2026-03-27 | Leo Farrell | Scunthorpe → Barnsley | Return from loan |
| 2026-03-02 | J. Lewis | Barnsley → Lexington | Free agent |
| 2026-02-27 | Leo Farrell | Barnsley → Scunthorpe | Loan |
| 2026-02-22 | B. Cotter | Barnsley → Derry City | Free agent |
| 2026-02-21 | B. Cotter | Notts County → Barnsley | Return from loan |
| 2026-02-07 | Xu Bin | Wolves → Barnsley | Loan |
| 2026-02-02 | Connor Barratt | Barnsley → Galway United | Loan |
| 2026-02-01 | D. Keillor-Dunn | Barnsley → Wrexham | Transfer |
| 2026-02-01 | T. Bradshaw | Oxford United → Barnsley | Loan |
| 2026-01-29 | Fábio Jaló | Barnsley → Oldham | Loan |
| 2026-01-29 | T. Chirewa | Wolves → Barnsley | Loan |
| 2026-01-25 | S. Banks | FC St. Pauli → Barnsley | Loan |
| 2026-01-16 | C. Lennon | Middlesbrough → Barnsley | Transfer |
| 2026-01-14 | K. Łopata | Barnsley → Walsall | Loan |
| 2026-01-14 | O. Goodman | Crystal Palace → Barnsley | Loan |
| 2026-01-13 | N. Farrugia | Barnsley → Dundee Utd | Transfer |
| 2026-01-13 | M. Mahoney | Barnsley → QPR | Return from loan |
| 2026-01-08 | Caylan Vickers | Barnsley → Brighton (U21) | Return from loan |
| 2026-01-07 | J. Russell | Barnsley → Mansfield Town | Loan |
| 2026-01-05 | K. Łopata | Bristol Rovers → Barnsley | Return from loan |
| 2026-01-05 | E. O'Connell | Wrexham → Barnsley | Free agent |
| 2026-01-04 | C. O'Keeffe | Stockport County → Barnsley | Return from loan |
| 2026-01-02 | B. McCann | Alfreton Town → Barnsley | Return from loan |
| 2026-01-01 | B. McCann | Barnsley → Doncaster | Transfer |