Justin Theroux and Prince William's princesses have at least one thing in common: they both know that a polished blazer can upgrade any casual outfit.

At LAX in L.A. on Saturday, Jennifer Aniston teamed a navy, brass buttoned Balmain blazer with a white tee and baggy boyfriend jeans by Vivienne Westwood. The 43-year-old actress accessorized her in-flight outfit with a long pendant necklace, a brown belt and white Superga sneakers.

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Kate Middleton first wore a similar Emilio Pucci waist-length blazer in London, England on March 15 when she paid a visit to the country's Olympic Field Hockey team. The Duchess of Cambridge, 31, wowed fashionistas when she paired the jacket with tangerine J Brand jeans, black pumps, a white tee and a scarf.

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A double-breasted navy blue blazer isn't the only instance of Hollywood stars and the royal sharing the same taste. On June 3, Middleton wore a long-sleeved, bright red Alexander McQueen dress with a pleated skirt to Queen Elizabeth II's Diamond Jubilee River Pageant in London, England. Last August, Kim Kardashian, 31, sported the sleeveless version of the designer's frock.

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This article originally appeared on Usmagazine.com: Who Wore It Best: Jennifer Aniston or Kate Middleton?