Camelot has announced changes to the National Lottery’s Lotto game from October that it says will drive more shoppers in store.

A new Millionaire Raffle will guarantee a £1m prize in every draw and customers with two matching numbers will get a free Lucky Dip ticket for a future draw. The average jackpot is expected to triple on the current game and the limit on the number of rollovers will be removed. The number of balls to choose from will also increase from 49 to 59.

But some retailers are worried that they will lose customers because the number of balls to choose from is higher, making it harder to win.

“I think it will be detrimental to sales. The decision to increase the ball number from 49 to 59 is a bad move. When customers realise their chances have dropped, why will they play?” Masqood Akhtar, from Blackthorn News & Food in Roterham said.

“Some of my regular customers have already stopped playing and the changes don’t come in until October. My store used to close at 7.30pm, but when the Lotto increased the price from £1 to £2 our sales dropped, now we close early.”

However, Camelot report that retail sales are up 7% since 2013/14 and make 80% of the National Lottery sales – despite the rise in digital sales.

“The fact that they’ve made the odds even bigger is just going to put people off. And the addition of a free go just makes it more confusing. They need to streamline it for customers,” Jessica Nandhra, Loco Carlos in Leeds.

“They aren’t going to change it back, but our sales will change. Since they’ve increased the Lottery to £2, customers have switched to scratchcards. We make over £1,000 on them. But they should have just left it all alone.”

However, Duncan Malyon, sales director at Camelot, said: “The changes are an opportunity for retailers to increase their sales and generate traffic into store.”