| 2026-09-30 | Valentin Dimitrov | Spartak Varna → Septemvri Sofia | Loan |
| 2026-09-22 | A. Abou | Septemvri Sofia → CSA Steaua Bucureşti | Transfer |
| 2026-09-07 | P. Georgiev | Septemvri Sofia → Marek | Free agent |
| 2026-09-06 | N. Iliev | Botev Plovdiv → Septemvri Sofia | Loan |
| 2026-08-30 | S. Vulikić | Levski Sofia → Septemvri Sofia | Loan |
| 2026-08-18 | Pedrinho | Ferroviario → Septemvri Sofia | Loan |
| 2026-08-03 | V. Hamdiu | Septemvri Sofia → Rapperswil | Free agent |
| 2026-08-01 | Pedro Igor | Botev Plovdiv → Septemvri Sofia | Loan |
| 2026-07-31 | P. Gospodinov | Spartak Pleven → Septemvri Sofia | Free agent |
| 2026-07-29 | D. Ivkič | Septemvri Sofia → Brinje-Grosuplje | Free agent |
| 2026-07-26 | B. Fourrier | Septemvri Sofia → Ural | Transfer |
| 2026-07-07 | André Filipe Rio Liberal | Pacos Ferreira → Septemvri Sofia | Transfer |
| 2026-07-05 | M. Stamatov | Septemvri Sofia → Torpedo Kutaisi | Free agent |
| 2026-06-30 | K. Kolev | Septemvri Sofia → Chernomorets 1919 Burgas | Free agent |
| 2026-06-30 | Y. Georgiev | Septemvri Sofia → Arda Kardzhali | Free agent |
| 2026-06-30 | B. Marinov | Septemvri Sofia → Vihren | Free agent |
| 2026-06-30 | Viktor Dobrev | Septemvri Sofia → Septemvri Sofia | Transfer |
| 2026-06-30 | A. Vutov | Septemvri Sofia → Septemvri Sofia | Transfer |
| 2026-06-30 | Pedro Ferreira | Paredes → Septemvri Sofia | Free agent |
| 2026-06-30 | B. Penchev | Botev Vratsa → Septemvri Sofia | Free agent |
| 2026-06-29 | G. Varbanov | Septemvri Sofia → Varbanov Georgi | Free agent |
| 2026-06-29 | Y. Georgiev | Septemvri Sofia → Georgiev Yanko | Free agent |
| 2026-06-29 | B. Marinov | Septemvri Sofia → Marinov Borislav | Free agent |
| 2026-06-29 | V. Hamdiu | Septemvri Sofia → Hamdiu Valon | Free agent |
| 2026-06-29 | D. Ivkič | Septemvri Sofia → Ivkic Dominik | Free agent |
| 2026-06-29 | Viktor Dobrev | Septemvri Sofia → Dobrev Viktor | Free agent |
| 2026-06-29 | B. Stoichkov | Septemvri Sofia → Stoichkov Borislav | Free agent |
| 2026-06-29 | Z. Atanasov | Lokomotiv G. Oryahovitsa → Septemvri Sofia | Return from loan |
| 2026-06-29 | S. Stojanović | Septemvri Sofia → FK Spartak Zdrepceva KRV | Return from loan |
| 2026-06-29 | N. Genchev | Septemvri Sofia → Genchev Nikola | Free agent |
| 2026-06-29 | V. Ivanov | Belasitsa → Septemvri Sofia | Return from loan |
| 2026-06-29 | P. Gospodinov | Spartak Pleven → Septemvri Sofia | Free agent |
| 2026-06-29 | Aleksandar Sirakov | Septemvri Sofia → Sirakov Aleksandar | Free agent |
| 2026-06-29 | W. Hamdiji | Septemvri Sofia → Hamdiji Walloon | Free agent |
| 2026-06-29 | Dimitar Marinov | Septemvri Sofia → Marinov Dimitar | Free agent |
| 2026-06-29 | V. Agushev | Septemvri Sofia → Agushev Vasil | Free agent |
| 2026-06-29 | P. Milenov | Septemvri Sofia → Milenov Petar | Free agent |
| 2026-06-29 | D. Chelebiev | Septemvri Sofia → Chelebiev Dimitar | Free agent |
| 2026-05-31 | Aleksandar Sirakov | Septemvri Sofia → Septemvri Sofia | Raise |
| 2026-03-24 | A. Aruna | Septemvri Sofia → Grobiņa | Free agent |
| 2026-03-15 | F. Herard | Universidad O&M → Septemvri Sofia | Free agent |
| 2026-03-11 | M. Bibishkov | Septemvri Sofia → Vancouver FC | - |
| 2026-02-21 | V. Hamdiu | Unirea Slobozia → Septemvri Sofia | Free agent |
| 2026-02-11 | Z. Atanasov | Septemvri Sofia → Lokomotiv G. Oryahovitsa | Loan |
| 2026-02-09 | A. Abou | Feirense → Septemvri Sofia | Free agent |
| 2026-02-09 | V. Ochayi | Septemvri Sofia → Ashdod | Transfer |
| 2026-02-05 | K. Serber | Septemvri Sofia → Hamrun Spartans | Free agent |
| 2026-01-28 | V. Ivanov | Septemvri Sofia → Belasitsa | Loan |
| 2026-01-27 | A. Abou | Feirense → Septemvri Sofia | Free agent |
| 2026-01-26 | V. Hamdiu | Unirea Slobozia → Septemvri Sofia | Free agent |
| 2026-01-22 | N. Krastev | Slavia Sofia → Septemvri Sofia | Free agent |
| 2026-01-22 | D. Ivkič | Koper → Septemvri Sofia | Free agent |
| 2026-01-22 | E. Ribeiro | Amora → Septemvri Sofia | Free agent |
| 2026-01-16 | S. Stojanović | FK Spartak Zdrepceva KRV → Septemvri Sofia | Loan |
| 2026-01-13 | K. Kolev | Dobrudzha → Septemvri Sofia | Free agent |
| 2026-01-13 | V. Dotsev | Septemvri Sofia → FK Minyor Pernik | Free agent |
| 2026-01-06 | Moi Parra | Septemvri Sofia → Antequera | Free agent |