According to research from Deloitte, items from the designer and other luxury goods now cost less in Britain in dollar terms than anywhere else.
It linked the trend to the fall in sterling since the Brexit vote, which has boosted tourists’ spending power.
The pound has fallen more than 17% against the dollar since June.
According to the research, which was prepared for the Wall Street Journal, a Speedy 30 handbag from Louis Vuitton cost 645 pounds in London as of 7 October, or 802 pounds.
That compared to 760 pounds ($850) in Paris and $970 in New York. In China the bag cost 7,450 yuan, or $1,115.
Nick Pope, fashion and luxury lead at Deloitte, told the BBC a "period of affordability" after the EU referendum vote was proving a "demand pull" for tourists, who account for more than half of the UK’s luxury goods market
The trend in luxury pricing in the UK is being driven mainly by the depression on the sterling - thus making the same item more affordable in the UK market than in any other major luxury market, he said.
People don’t like paying more for the same product.
That chimes with official statistics that show overseas residents made 3.8 million visits to the UK in July - up 2% on the same month last year. In total, they spent some 2.5bn pounds.
The fall in sterling has pushed up the price of some everyday goods, but Deloitte said luxury retailers had kept prices stable for fear of scaring off consumers.
It said 64% of comparable luxury products were now cheaper in the UK than anywhere else.
Other examples include Balenciaga’s Foulard Fringe Dress, which currently costs about $400 less in the UK than in the US.
A Brunello Cucinelli cashmere v-neck for men, meanwhile, now costs 650 pounds, or $843, in Britain compared to $942 in France and $995 in the US.
Mr Pope warned the discounts would not necessarily last, however, adding that a small number of brands had already put prices up.
"Luxury brands are usually - and rightly - cautious about en masse pricing adjustments," he said.
"But if over six to 12 months this sterling position becomes the ’new normal’ - and hence margins are under continued pressure - I would expect more brands to respond with pricing adjustments."