The singer – who previously has lent his soulful vocals to tracks by musical heavyweights including Beyoncé, Drake, Solange and Kanye West – beat favourites including Kate Tempest, Loyle Carner and Stormzy to take the prize.
The long-time collaborator became a fully-fledged recording artist in his own right with his debut album, Process, released in February 2017 via Young Turks.
Centered around the death of his mother and worries for his own health, the critically acclaimed album picked up the £25,000 prize in what presenter Lauren Laverne described as, the 'longest deliberation from our judges ever'.
Actor Idris Elba presented Sampha with his £25,000 prize at the ceremony in London, where the singer performed a stunning version of (No One Knows Me) Like the Piano.
When asked what he would do with the prize money, the unassuming singer replied: 'Put it away? Save it up? Saving is always good,' before adding that he would be celebrating with friends and family with 'a couple of drinks.'
The Mercury Prize 2017 shortlist is below:
Alt-J – Relaxer
Blossoms – Blossoms
Dinosaur – Together, As One
Ed Sheeran – Divide
Glass Animals – How To Be a Human Being
J Hus – Common Sense
Kate Tempest – Let Them Eat Chaos
Loyle Carner – Yesterday’s Gone
Sampha – Process
Stormzy – Gang Signs and Prayer
The Big Moon – Love in the 4th Dimension
The xx – I See You