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BANANA REPUBLIC SKIRT
Kate rarely wears print, so when she was spotted in this colorful circle skirt at a London event for Heads Together (a campaign to combat mental illness), it caught everyone's eye – and sold out – immediately.
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TEMPERLEY LONDON SKIRT AND TOP
And if that tax refund is generous this year, you can afford the outfit she wore to a garden party in honor of Queen Elizabeth's birthday, which includes a $2,995 skirt and $1,525 crop top.
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For her first public appearance after giving birth to Princess Charlotte, went with her comfy, tried-and-true classic (seriously, she really loves this look). She sported a Me+Em Breton scoop-neck top that almost instantly racked up a two month waiting list. Oh, the power of her polo-wear. (And of course, Prince George’s blue cardigan also sold out overnight.)
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Another non-maternity look for the six-months-pregnant Princess, who caused a craze for the Hobbs “Animal” shirtdress after she wore it at an event for The Fostering Network in January.
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She visited the M-PACT Plus Counseling program in London in July 2014 wearing a pleated Goat dress cinched at the waist with a silver-ring belt. Guess everyone thought the same thing: “I need this for the office – stat!”
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DIANE VON FURSTENBERG WRAP DRESS
In April 2014 she visited Australia’s Blue Mountains in a Diane von Furstenberg wrap dress, which sold out in eight minutes after she smiled for the cameras.
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She may get to borrow jewels from the Queen, but Kate’s not above sporting a piece with a $35 price tag from Zara, which she wore with her fave (Roland Mouret gown) to the Mandela: Long Walk to Freedom London premiere in December 2013.
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ORLA KIELY PRINTED DRESS
At a November 2013 event, Kate recycled her Orla Kiely “Birdie (she wore it first in 2012), which (once again) sold out within minutes.
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Everyone lost their minds when the first official photos of Prince George were released a month after his birth. The family dogs! The fact that Kate’s dad snapped the photo! That stunning purple dress! So it’s no surprise her Séraphine frock was long gone before many could get their hands on it. The designer told PEOPLE they sold over 100 dresses between the hours of 2:00 a.m. and 7:00 a.m.!
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TOPSHOP ALINE DRESS
Six months pregnant with Prince George in April 2013, Kate visited the Harry Potter studio tour in London in a polka dot frock from TopShop. A bargain plus a universally cute design? Shoppers never even had a chance.
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L.K. BENNETT HEELS
You could say she loves her L.K. Bennett “Sledge” heels a lot (she wore them three times in one week during the Queen’s Jubilee in 2012) – in fact, she must have so many pairs at this point, we’re guessing she might be the reason they keep selling out.
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Kate stopped by Belfast City Hall in March, 2011 wearing the quintessentially British coverup: a Burberry trench. Also standard: How fast shoppers snapped it up once they saw her wearing it.
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The second the couple debuted their official engagement portrait, taken by famed fashion photographer Mario Testino, everyone wanted Kate’s three-quarter length sleeve Reiss “Nanette” gown. In fact it was in such high demand, the designer reissued the dress a month later and bidding prices on Ebay were more than double the initial retail price.
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ISSA WRAP DRESS
What could be more fitting to match her stunning sapphire engagement ring than a tasteful, form-fitting Issa wrap dress to the engagement announcement? This could be pegged to the beginning of the Kate Effect, because the dress sold out instantly and even prompted the British designer to collaborate with Banana Republic to create a lower-priced replica (which of course, was gone within a week).