Online spending rose to over £4.5 billion in May, representing an increase of 1.6 per cent on April's figure.
Figures from the IMRG Capgemini e-Retail Sales Index revealed that clothing, footwear and accessories all received a boost as a result of summer fashion sales.
But electrical sales fell by ten per cent and sales of alcohol dropped by 11 per cent.
The drop in alcohol was blamed on the lack of a big side in the FA Cup final and the presence of no home nations at this summer's Euro 2008 championships.
The total spending represents the equivalent of each person in the UK spending £73 in May and a year-on-year increase of 30 per cent.
Anthoula Madden, vice-president of Capgemini UK's Consumer Products and Retail team, said that shoppers were being more careful with their funds because of the credit crunch.
She said it should warn retailers to be more innovative with their promotions and provide a good service to their existing customers.
Meanwhile, general retail spending rose by 3.5 per cent last month.
