After undergoing medical tests and signing forms in the morning, the former Liverpool fullback was presented to fans and the local media at 12:30pm at the Santiago Bernabeu.
After being introduced and welcomed by president Florentino Perez, Alexander-Arnold delivered his own introduction in perfect Spanish.
He said, "Good afternoon, thank you for giving me this opportunity. Signing for a club like Real Madrid doesn't happen every day. I'm very happy. I'm eager to show my game to the Real Madrid fans.
"I'm aware that I have a huge responsibility, but I'm ready to give it my all. I'm eager to win many titles and be a champion, grow, and enjoy life with the best. Thank you, and Hala Madrid!"
Welcome to Real Madrid
Before Trent's words, he was welcomed by Real president Florentino.
"Dear Trent Alexander-Arnold, good afternoon and welcome to Real Madrid City. A player who has won everything and is one of the best defenders in the world has arrived at Madrid. He has become a legend at Liverpool and wants to continue to build on his legacy at Madrid. We welcome Trent Alexander-Arnold.
"I want to express our gratitude because we know what playing for Real Madrid means to you. We'll never forget it. You're coming from Liverpool, a club we love. You've won nine titles at Anfield. All of this in 354 matches.
"You must be proud of everything you've achieved, both at Liverpool and with England. Your family has been there at all these stages of your life. We know how much they mean to you. They represent your hard work and effort. They're here to support you on one of the most exciting days of your life. You're now part of Real Madrid.
"It's the most beloved and successful club in the world, the club with 15 European Cups. Your talent and capacity for sacrifice convince you that you'll achieve it here. The Bernabéu awaits you; you'll experience unique moments there. You'll fall in love with its magic. At Madrid, you'll find a great family. A great friend of yours is there: Bellingham. In addition to being great players, they're all Real Madrid fans. You'll soon understand what Real Madrid is all about. Our next challenge is the Club World Cup."
Florentino concluded: "You'll see what Real Madrid represents to millions of Real Madrid fans. The power of the fans fuels this myth. One of the greatest figures in world football is joining our club. Thank you, Trent, for coming to your new home. Thank you very much."