The Masters, snooker's most prestigious invitation event, will be sponsored by Saga Insurance.
The tournament, which was sponsored by Rileys last year after being without a backer in 2004, starts on 15 January.
"We're thrilled to welcome them on board - this partners snooker with a major new business sector," said World Snooker chairman Sir Rodney Walker.
World Snooker has also said it will name the new sponsor for April's World Championship on Monday.
Snooker has been forced to look for new financial backing after government legislation banned tobacco sponsorship.
The Masters, which features the world's top 16 plus two wild cards, had a long association with cigarette brand B&H but has had to find fresh sponsorship.
"We're putting a new commercial structure in place for the game of snooker," said IMG senior vice-president Andrew Wildblood.
"Both World Snooker and Saga see this commitment as being the first building block for Saga to become a partner, through making a long-term commitment to the sport."
IMG, a sport marketing firm, brokered the new deal.
Saga provides a variety of products and services aimed at people aged 50 and over.