Tesco has been voted worst UK supermarket in an annual poll of 11,000 consumers.
The high street behemoth was bottom of a Which? survey of nine major supermarkets scoring just 45% and receiving poor marks for its pricing, store environment, quality of fresh produce and customer service.
Waitrose topped the poll, receiving a customer score of 82%, including five-star ratings for its customer service and the quality of its fresh produce.
More than 11,000 Which? members rated the supermarkets with scores based on customer satisfaction and the likelihood they would recommend it to a friend.
Discount supermarkets Aldi and Lidl came second and third with scores of 74% and 69% respectively, beating some of their bigger rivals such as Morrisons (59%), Sainsbury's (58%) and Asda (53%).
Aldi and Lidl were the only supermarkets to get four-star ratings for their pricing, with 97% of Which? members saying they both offer good value.
Fourth place went to Marks & Spencer with 68%, while The Co-operative scored just above Tesco with 48%.
Ocado took top spot in the online ranking with 81%, followed by Waitrose (74%), Sainsbury's (71%), Tesco (63%) and Asda (61%).
The poll revealed that consumers' biggest irritation when supermarket shopping is not being able to compare prices because of different unit measurements, with 37% reporting that this annoyed them.
Members also wanted supermarkets to keep special offers simple, with 55% preferring straight discounts ahead of other offers such as petrol vouchers (16%) or buy-one-get-one-free deals (11%).
Which? executive director Richard Lloyd said: "Which? research shows that rising food prices are one of consumers' top financial worries, so in these tough economic times it's understandable that supermarkets scoring well for value for money are being ranked so highly in our league table.
"But our survey also found that consumers think supermarkets are not doing enough to help shoppers on tight budgets, with only one in five Which? members saying they trust retailers to charge a fair price for food.
"We want supermarkets to make a firm commitment to treat their customers fairly by scrapping misleading price promotions and introducing clear, consistent unit pricing so busy shoppers can spot the real bargains."
A Tesco spokeswoman said: "Millions of customers shop regularly with Tesco and we are always looking at ways to improve their shopping experience.
"We have made a £1 billion commitment to make Tesco better for our UK customers and since this survey in October 2012, we have had an encouraging Christmas and New Year and are delivering further improvements this year.
"We are focusing on improving the look of stores, giving customers great value and making sure they can get all the help they need, which is why we've recruited 8,000 more colleagues."