The Grammy-nominated R&B artist is taking part in the special performance to help raise money for Shelter, a charity that works to help people struggling with homelessness and bad housing. Shelter reports that there are currently 320,000 homeless people in Britain.
Tickets can be bought for £45 via a ballot system, with all proceeds going to Shelter.
Smith said: “I’m thrilled to perform at this year’s Shelter music gig, at such an iconic and intimate venue, and help raise money that supports the amazing work the charity does fighting homelessness.
“Everyone should have a safe place to call home and buying a ticket will make a massive difference to people facing homelessness this Christmas.”
Doors for the event will open at 7pm, with guest support acts to be revealed on the night. Fans can purchase a maximum of four tickets. The ballot can be entered here.
The ticket ballot launches today (20 November) at 11am and is open until 9am on Monday 25 November. Successful applicants will be noticed from 1pm the same day.
To donate to Shelter’s Christmas appeal visit www.shelter.org or text SHELTER to 70030 to donate £3.