The sale of UK sandwich chain Pret A Manger is set to attract a pricing multiple as much as 60% higher than originally expected at a time when other mid-market private equity transactions are struggling to find financing.

NM Rothschild, the investment bank mandated by Pret earlier in the year to conduct the sale, initially marketed the company at a value of between £350m (€502m) and £400m, according to a source involved in the auction. Pret is now expected to sell for between £400m and £450m, said the source.