Helen Dickinson, the new director general of the BRC, said the "stand-out" online performance came after slower momentum in the previous few months.
She said: "Many valued the ease and convenience of shopping online during the Christmas period. The surging popularity of tablets and smartphones giving even better access is a major factor."
She also said shoppers felt much more comfortable putting their credit card details into their mobile phones.
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No energy supplier scored highly enough to be awarded the Which? recommended provider status.
ITV said the move was to "focus our efforts on our digital platforms, in support of the main show."
A freezing, frosty night for some of us, milder for others