The apex court in a unanimous decision dismissed seven petitions that had been filed challenging Ruto's win.
The duo who were running on a UDA ticket beat Raila Odinga of Azimio la Umoja, George Wajackoyah of Roots Party, and David Mwaure of Agano Party.
According to the Independent Electoral and Boundaries Commission (IEBC), Ruto got 7.18 million votes (50.49 per cent) while Odinga got 6.94 million votes (48.85 per cent).