Kate Middleton knows how to make sweatpants look good: See her best casual looks

Looking like a royal isn't necessarily contingent on spending thousands of dollars on elegant designer gowns, flawless blowouts and high heels.

Take Kate Middleton, for example. As much as she is a style icon, and can rock an Alexander McQueen masterpiece and headpiece to match, the duchess is also known for perfecting a casual look. Whether for an off duty event like attending a polo match or for hitting the courts as part of a royal engagement, Kate's down-to-earth style is just as easy to emulate as she makes it out to be.

The mom-of-three, who is known to favor affordable brands such as Zara, Topshop and the Gap, proves you can look just as polished by adding a blazer and a pair of heels to any ouftit. Just a few months ago, the royal took the casual white tee up a notch by adding a pair of trousers, olive blazer and heels. And just last week, she donned a simple $50 J.Crew sweater, which she polished off with sleek designer combat boots.

Scroll through above to see Kate's best casual moments, from skinny jeans to polos to, yes, even sweatpants!

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