Overview

• Aldi has been ranked the cheapest UK supermarket for the 16th consecutive month, with a basket of 82 staple items costing £135.48 in May.
• Tesco shoppers without a Clubcard pay an average of £17 more per weekly shop than customers at Aldi, while Clubcard users still incur a £14.78 premium.
• If the current price gap persists, Tesco Clubcard customers would spend an extra £768.56 over a year compared with Aldi shoppers.
• For a larger 198-item basket that includes branded products unavailable at discounters, Asda emerges cheapest at £485.79, with Tesco Clubcard second at £496.59 and Waitrose priciest at £559.02.
• Asda’s grocery market share has fallen to 12.1%, its lowest level since 2011, and boss Allan Leighton warns there is "a long way to go" in the chain’s turnaround.