Department store John Lewis sales surged 14.9% to £60.8m last week as Olympic fever once again boosted sales.

John Lewis director of selling operations, Region B David Barford said: “The final week of the London 2012 Olympic Games and the weekend celebrations certainly played a part in our success.”

In the week to August 11, the electricals, home and technology category had a strong week, with telecoms rocketing 148.8%, consumer electronics accessories up 40.4% and large electricals growing 16.1%.

Fashion advanced 18.9% with sports sales surging 177.7%. John Lewis said its London 2012 merchandise in particular had been “a huge success”.

Kidswear and babywear “had a really good week” with sales up 147%.

Men’s branded casualwear sales grew 29.8%. The best performance in womenswear came from the JL and Weekend brands, which grew 28.2%.

Home sales increased 7% with home and gift collection jumping 184.2% within the category.

John Lewis reported that 18 branches had increases in the week, with Croydon up 50%, Oxford Street 18.9%, and Leicester 13.4%. Sales at Stratford City - the shopping centre located adjacent to the Olympic Park - were not given because it has been open for less than a year.

John Lewis.com sales increased 36.4% with “good solid performances from all three directorates”.

Barford said: “We have had a really positive response from our customers on new ranges so with the weather more mixed this week, I think we can look forward to another strong week of trade.”

The strong performance by Team GB also boosted sales at sister retailer Waitrose.

The upmarket grocer’s sales rose 12% as the Olympic “feel-good factor continued to sweep the nation”, said Waitrose retail director David Jones.

Fresh produce sales sprinted 15.3% ahead of last year, and beers, wines and spirits jumped 12.7%.

Waitrose said it benefited from the nation toasting its sporting heroes, with champagne sales up 35%.

The grocer’s Stratford City branch set a record for the number of customers served.

Online orders at Waitrose.com were up 54.4% and ready meals up 11% “as homes throughout Great Britain remained glued to their television sets to see where the next medal would come from”.