Generally speaking, there are two main types of fill, or stuffing, that go into a comforter. First, there are down comforters, which are filled with soft materials like cotton or goose down feathers for a fluffy, plush feel. (But tread lightly: When looking at down comforters, it’s important to make sure that the company is using responsible, sustainable, and animal-safe practices when they source their down.) However, if you struggle with allergies, avoid feather-filled down comforters, says Weiss.

Unlike down comforters, down alternative comforters—which are typically just as soft—are stuffed with synthetic materials like polyester. That being said, most down alternative comforters are hypoallergenic and less likely to retain dust, says Weiss.

Another consideration when buying your comforter is fill power, also known as gram-per-square-meter (GSM). A comforter’s fill power, or GSM count, refers to the weight of a comforter. Typically, if you’re a hot sleeper, you’ll want to go for a lower GSM count. And if you run cold? Opt for a heavier comforter with a higher GSM count.