Multiple Grand Prix winner George, 27, heads into his eighth season in F1 whilst Kimi, 19, continues into his second year.
Both are graduates of the team’s junior system, having joined the programme in 2017 and 2019 respectively.
“Confirming our driver line-up was always just a matter of when, not if,” said Toto.
“We wanted to take our time, handle the negotiations properly and make sure everyone, on all sides, was happy. I'm pleased we have done that.
“George and Kimi have proved a strong pairing and we're excited to continue our journey together.
“Our focus is now on the final six races of the year, as we fight for second in the Constructors', and onwards to 2026 and a new era in F1.”