Cheltenham's showpiece Gold Cup race will see a bumper prize fund of £400,000 next year.
The purse will rise from £350,000 as the blue riband event at the Cheltenham Festival retains its totesport sponsorship for the next four years.
The race has been sponsored by totesport since 1980.
Peter McNeile, commercial manager at Cheltenham, said: "The totesport Gold Cup will continue to be the most sought after prize in jump racing."
The event is raced over three miles, two and a half furlongs at Cheltenham's Prestbury Park.
It has been won by some of the most famous horses in National Hunt history, including Dawn Run (1986), Desert Orchid (1989) and more recently Best Mate, who recorded a three-timer from 2002 to 2004.
The 2006 totesport Gold Cup will be run at Cheltenham on Friday 17 March, the last day of the Festival.