The Spaniard released a heartfelt statement reflecting on the highs and lows of his footballing journey while expressing gratitude to his family, team-mates, and supporters.
Writing via his official Instagram account, Tello said: "Today it is time to say goodbye to a part of my life. After so many years, so many matches, so many dressing rooms, so much joy and also difficult moments, the time has come to bring an end to professional football.
"Football has given me everything. It has allowed me to fulfil dreams that once seemed impossible, meet people I will carry with me forever, and experience moments that will stay in my memory for a lifetime. I have been fortunate enough to wear shirts that mean the world to me and to share the journey with team-mates, coaches, club staff, friends, and above all, my family."