Former world champion Raikkonen will part ways with the Italian team to rejoin Sauber at the end of this season.
The 38-year-old has been with Ferrari four years after rejoining them for a second spell in 2014.
Now the Finn will rejoin the team that he made his Formula 1 debut with back in 2001, having signed a two-year contract.
Going the other way is 20-year-old Leclerc and he’ll partner Sebastian Vettel at the Scuderia next season.
This is the first time a driver from Monaco will race for Ferrari.
And former Sauber and Ferrari driver Felipe Massa is backing the young protege will be a huge success.
The Brazilian posted a picture on Instagram alongside Leclerc and congratulated him for his achievement.
“Bravo @charles-leclerc congratulations!! It’s just the beginning!” he wrote.
“I am sure you will be on the top very soon. Future champion of F1, god bless you.”
It is perhaps testament to the Monegasque driver’s ability that Massa has predicted him to do something he could never do, become a Formula 1 champion.
Leclerc has big boots to fill, as Raikkonen is the last ever Ferrari driver to win the world championship in 2007.
Based on his debut F1 season, he’s more than capable of becoming a future star.
The member of Ferrari driver academy took to Twitter to express his delight.
“Dreams do come true. I will be eternally grateful to Ferrari for the opportunity given,” he wrote.
Leclerc also paid tribute to his late father and godfather Jules Bianchi (also previously of Ferrari) who tragically lost his life in 2015, nine months after crashing in the Japanese Grand Prix.
“To a person that is not part of this world anymore but to whom I owe everything of what is happening to me, Papa,” said Leclerc.
“To Jules, thank you for all the things you learnt me, we will never forget you, and to all the persons that supported me and believed in me.
“I will work harder than ever to not disappoint you. But first, there is a season to finish with an amazing team that gave me the opportunity to fight and show my potential.”