Changing your duvet cover is a wonderfully effective way to transform the look of your bedroom – this one simple swap can switch up your color palette, add a bold dash of pattern, or shift the overall theme of your decor. But what are duvet covers? If you're unfamiliar with these versatile bedding accessories, a duvet cover is a simple sheath of fabric used to encase a thicker blanket. It's like a pillowcase for your comforter! Quality comforters can be expensive, so a duvet cover makes it easy to experiment with different styles at a much lower cost. Duvet covers are also much quicker and easier to clean, able to be thrown right into a standard home washer. We've collected our favorite duvet covers below – from budget to luxury, in a world of creative fabrics and colorways.