The survey, based on the experiences of 2,072 Amazon shoppers from 11 countries across the continent, showed that one in three British and French shoppers visit online stores more than twice a week, while three in 10 used the Internet to shop more than 10 times a month.
More worryingly for UK businesses, the survey also showed that 40% of UK users shop online during working hours - compared to a 31% average across Europe as a whole.
Convenience and around-the-clock availability were the two biggest attractions for shopping online rather than in the high street, with cost only the fourth most important factor, the survey found.
Amazon believes online retailers can improve customer service and boost sales by better understanding different markets.
"We have to learn from the nuances of each nation's shopping habits to see how we can serve our customers better over the next three years and beyond," said Amazon.co.uk managing director Robin Terrell.