Loyalty card scheme Nectar aims to sign up another 20 partners over the next three years, and is targeting fashion, DIY and beauty retailers.
Nectar - which already counts Sainsbury's, Debenhams and Adams as participants - brought Allsports on board as its ninth partner on Monday and is in discussions with other big retail names.
Rob Gierkink, chief executive officer of Nectar operator Loyalty Management UK, refused to name any of the prospective partners. But he said Nectar would only sign up one retailer in each sector to guarantee exclusivity.
Nectar has met its first-year target of signing up 50 per cent of UK households, and claims to have more than 13 million accounts in the UK.
But some analysts have been sceptical about the success of Nectar, and point to Sainsbury's slipping market share.
Gierkink would not comment on a correlation between Nectar and Sainsbury's performance, but said: 'I would argue with anyone that what we have is better than what Tesco has.'
At Tesco's interim results on Tuesday, chief executive Sir Terry Leahy reiterated his claim that Tesco Clubcard is the UK's favourite loyalty scheme.