Waitrose has been named Britain's top supermarket for customer satisfaction for the second year running, according to a national survey published by the consumer experience company Market Force Information.
Aldi also overtook Marks & Spencer for the first time to become the nation's second favourite supermarket, according to research based on the experiences of 6,648 shoppers.
While premium and discount brands vied for first place this year, Sainsbury's and Morrisons came in fourth and fifth place.
Each supermarket brand was rated by how satisfied consumers were with their last shopping experience at the store, and how likely they would be to recommend it to others.
Waitrose was ranked first for nearly all satisfaction indicators, but was beaten by Aldi for the time it takes customers to complete their shopping at the checkout.
However, five of the big six supermarkets experienced dips in customer satisfaction scores from 2015, with one in 10 shoppers saying that they were dissatisfied with their latest shopping experience.
Only Tesco, Britain's biggest supermarket chain, recorded an increase in customer satisfaction.
Commenting on the figures, Market Force's chief strategy officer, Cheryl Flink, said that the figures showed that the premium brands were still "winning the war for customers' hearts".
"But Aldi's entry into the top two shows how discounter chains are stealing market share from conventional supermarkets by delivering extremely well on value," she added.