Having been quoted briefly in a Mercedes press release that flagged his departure, Hamilton used an Instagram post on Saturday to give an extensive and more personal insight into his decision, and the thought process behind it.
After years of competing against the Maranello team, the seven-time world champion made it clear that driving for Ferrari has been a long-held ambition.
"It's been a crazy few days which have been filled with a whole range of emotions," he wrote.
"But as you all now know, after an incredible 11 years at Mercedes, the time has come for me to start a new chapter in my life, and I will be joining Ferrari in 2025.
"I feel incredibly fortunate, after achieving things with Mercedes that I could only have dreamed of as a kid, that I now have the chance to fulfil another childhood dream. Driving in Ferrari red."
Hamilton stressed how hard it was to decide to leave a company that he has been associated with since his karting days when he was supported by the Mercedes-backed McLaren team.
"Mercedes has been a huge part of my life since I was 13 years old," he wrote. "So this decision has been the hardest I've ever had to make.
"I'm incredibly proud of all that we've achieved together, and I'm very grateful for the hard work and dedication of everyone I have worked with over the years and of course Toto [Wolff], for his friendship, guidance and leadership.
"Together we have won titles, broken records and become the most successful driver/team partnership in F1 history. And of course, I cannot forget Niki [Lauda], who was a huge supporter, and who I still miss every day.
"I must also share my huge appreciation to the whole of the Mercedes-Benz board and everyone at the company in Germany and around the world for supporting me over these 26 years. But the time is right to make a change and take on a new challenge."
Hamilton compared the current circumstances with September 2012, when he surprised the F1 world by signing for Mercedes and ending his relationship with McLaren.
"I still remember the feeling of taking a leap of faith into the unknown when I first joined Mercedes in 2013," he noted.
"I know some people didn't understand it at the time, but I was right to make the move then, and it's the feeling I have again now. I'm excited to see what I can bring to this new opportunity and what we can do together.
"However, right now, I'm not thinking about 2025. My focus is on the upcoming season and getting back out on track with Mercedes.
"I am more driven than ever, I am fitter and more focused than ever, and I want to help Mercedes win once again. I am 100% committed to the job I need to do and determined to end my partnership with the team on a high.
"Thank you to all of you who have been on this journey with me, you have all lifted me up as I chase my dreams and I hope I can continue to make you proud. As always, sending you my love and positive energy."