It started with the "Kate Effect" — the phenomenon in which every piece of clothing the Duchess of Cambridge wears in public sells out almost immediately.
In 2015 alone, the "Kate Effect" brought in $205 million to the British economy, and Meghan Markle, who will marry Prince Harry on May 19, is expected to have the same effect.
A report in January suggested that Meghan Markle and Prince Harry's royal wedding could contribute a whopping $850 million to Britain's economy, including sales in fashion, memorabilia, hotels, and travel.
And it's not only in the U.K. that the duchess and Markle make an impact — they also have a love for Canadian designers and just like everything else they wear, when they don Canadian styles, they sell out fast!
If you don't want to play the roulette game of trying to nab a piece once they wear it, here are some of their favourite Canadian go-tos.
Erdem
Erdem has long been one of the Duchess of Cambridge's go-to fashion lines. "Kate's favourite Canadian designer is definitely Erdem," Christine Ross, an editor at What Would Kate Do?, told HuffPost Canada.
"Kate first wore one of his designs on her first royal tour [of Canada] in 2011, and has been wearing both bespoke, runway, and ready-to-wear styles ever since."
Erdem Moralioglu, the designer behind the eponymous label, was born in Montreal, and grew up splitting his time between the French Canadian city and Birmingham, England. He earned his B.A. in fashion at Toronto's Ryerson University.
Sentaler
The Duchess of Cambridge may have worn the brand first, but it is Meghan Markle who is a loyal customer.
"Many will remember this brand as popping up on the royal fashion map after Kate wore it on the [royal tour of Canada]," Amanda Dishaw, editorial director of Meghan's Mirror, told HuffPost Canada, "but Meghan has been a fan of the brand for years, wearing their warm alpaca outerwear to bundle up against the Toronto cold in the past."
Markle has also been spotted in Sentaler since becoming engaged to Prince Harry, wearing a gorgeous camel coat at St Mary Magdalene Church in Sandringham for the Christmas Day service with the Royal Family.
Birks
It isn't only Canadian clothing designers Meghan loves — she's also a fan of Canadian luxury jewelry store, Maison Birks. "Birks has featured prominently in Meghan's jewelry box, most notably in royal engagement photos and at several engagements since. We love how she is keeping true to pieces, brands and styles that she embraced before her royal life began," Dishaw said.
Just last month during a trip to Edinburgh, Markle sported two stacked Birks rings, the Birks Iconic Rose Gold and Diamond Snowflake Ring and the Birks Iconic Yellow Gold and Diamond Splash Ring. And in January, while visiting a London radio station, she wore Les Plaisirs de Birks Gold Bar Earrings and a Birks Rosée du Matin Diamond Gold Bar Ring.
Mackage
On her first official outing with Prince Harry in December, Markle wore a Mackage coat to battle the chilly Nottingham weather. And just as we've seen with the duchess' fashion choices, the coat was sold out in minutes.
Hugo Thibault, Mackage's communications director, explained Meghan's impact on Canadian fashion to CBC News, saying, "Our website traffic exploded. We had a 500 per cent increase today ... mostly all in Europe, because North America (was) just waking up."
Smythe
During her first tour of Canada, Kate Middleton turned to Toronto-based design team Christie Smythe and Andrea Lencznerof Smythe.
The Duchess wore a navy blazer with gold buttons as she left Heathrow Airport en route to Ottawa. She has since re-worn the blazer several times.
Markle too has worn Smythe, most notably one of the label's coats during her visit to a South London radio station in January.
"[Markle]'s owned this coat for over a year and has worn it previously," Lenczner and Smythe told Hello magazine. "We are so proud and flattered that it made it to her new home in London," the designers added.
Aritzia
You only get one chance to make a good first impression and that is exactly what Markle did when she and Prince Harry attended the 2017 Invictus Games opening ceremony in Toronto.
Even though they were seated apart, all eyes were on Markle who wore a Mackage leather jacket and matching burgundy Aritzia dress. She wasn't even engaged to Harry yet, but that didn't stop the dress from selling out fast!
Line
After it was announced that Prince Harry and Meghan Markle were engaged, the two appeared for a photo call at Kensington Palace. Markle stunned in a white coat by Canadian brand Line, also known as Line the Label.
"Meghan has an effortlessly chic sense of style, which we've always admired. We know this particular coat is one of her favourite pieces so we have officially decided to name it the 'Meghan.' We are elated for Meghan and wish her a lifetime of happiness with Prince Harry," John Muscat, president and co-founder of the label, told Today Style.
Banana Republic
Another label both ladies can get behind is Banana Republic. The Duchess of Cambridge has worn the company's designs for the launch of Heads Together, where she proved one can box while wearing a skirt.
Markle started wearing the brand before she became a part of the Royal Family and was photographed out and about in their skinny jeans and Sailor Stripe Boat-Neck Pullover.
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