Retailers in Britain are looking for substantial sales during the Queen's Diamond Jubilee celebrations.
Spending is expected to reach £823 million celebrating, nearly double the amount spent during last year's royal wedding between Prince William and Kate Middleton.
According to research by moneysupermarket.com, 32% plan to buy snacks, drinks and decorations to mark the Queen's 60 years on the throne, Reuters reports.
"The Jubilee has the potential to create a feel-good factor that lifts consumer confidence and persuades people to put their concerns to one side, even if only temporarily," said British Retail Consortium economist Richard Lim.
Tesco has already sold 93,000 paper crowns and tiaras, 15,000 miles of bunting and 400,000 Jubilee mugs. Nearly 30,000 Union Jack cushions have been sold in the past two weeks.
Tesco also expects to sell 2.86 million flags by the end of the weekend, which will see a flotilla of 1000 boats on the Thames, a pop concert at Buckingham Palace and a royal procession through London.
"This is the biggest week we have had since the Millennium in terms of party sales and we haven't even reached the weekend yet," said Tesco party range buyer Matt Compton.
"Anything with a Union Jack on it is selling like hot cakes."
Tesco also expects to sell 25 million units of beer, 1.6 million sausage rolls and 2 million punnets of strawberries.
The New West End Company expects more than 2 million visitors in the Oxford Street, Bond Street and Regent's Street area.
"We had a pretty tough quarter in UK retail and even in the West End, so this is certainly an upbeat message," said director Jace Tyrrell.
"We need some positive sales quite frankly; it's been a challenging time."