Magic Millions has expanded its women only owners bonus scheme to the $2 million MM Guineas for three-year-olds.

A bonus has been in place for horses owned solely by females in the $2 million Magic Millions 2YO Classic for a decade.

The bonus has in effect created a race within a race as it is paid to the first four female-owned horses.

It has proved popular because a horse can finish well back in the field and still earn a bonus on top of any prize money.

The new 3YO bonus will total $250,000 with $162,500 going to the first all women-owned horse over the line with $50,000 to the next horse.

The remaining money will be allocated to third home ($25,000) and fourth home ($12,500).

Magic Millions chief executive Barry Bowditch said it was an extra incentive for women to get involved with horse ownership.

"It also means some owners who miss a chance at a bonus in the 2YO Classic can get a shot at the extra money with a late bloomer," he said.

"The evolution of the Summer Carnival is a direct result of the program and fantastic prize money on offer."

"It's simply a quality carnival. The new Magic Millions races enable increased returns to owners and trainers."

Magic Millions day at the Gold Coast in January offers $10 million prize money.