Does the idea of a good night’s sleep feel like it’s just a dream? The secret to a better rest might lie in your mattress. 

And because you’re (hopefully) spending the recommended eight hours per night on it, it’s an important investment.

The good news: There’s no right or wrong way to choose a mattress, and you have plenty of options to pick from. It’s all about personal preference, says Sara Elizabeth Benjamin, M.D. , a neurologist and sleep medicine specialist at the Johns Hopkins Center for Sleep .

“Choosing your mattress is really individualized, and degree of firmness is a really personal decision. The most important thing is to try it out,” Benjamin says.

When is it time for a new mattress?

Most adults need seven to eight hours of sleep to feel refreshed—and if you’re spending eight hours per night on your mattress, it’s going to wear out over time.

“Realistically, you should replace your mattress every ten years or so,” says Benjamin.

But pay attention to your body’s cues: If you’re suffering from aches and pains, you may need to replace your mattress sooner.

“If you feel more sore in the morning, that may be a sign that your mattress is wearing out,” Benjamin says. “If you’ve recently slept somewhere else, like a friend’s house or hotel, and you feel like you were more comfortable than in your own bed at home, you might realize that your mattress isn’t what it needs to be.”

A sound investment: how to choose the best mattress

Like buying a new car or finding just the right pair of jeans, you should choose a new mattress in person. Here’s how to do it.

• Narrow your options based on body type . Some mattresses are recommended for people of a certain weight, so you make sure that your body type is appropriate for the mattress.
• Take your time . “Lie down on the mattress for more than just a few seconds,” Benjamin recommends. Consider visiting the store at off hours when you know it won’t be crowded, so you don’t feel self-conscious about getting cozy for a bit.
• Align with your partner . If you share a bed with someone and can’t agree on firmness, or if you or your partner have conditions like acid reflux where sleeping on an incline is important, look for mattresses that allow each side to be adjusted separately.
• Ask about warranties and return policies . Benjamin warns that sometimes the mattress that seems perfect in the store isn’t the right fit once you get home. “You should ask about any long-term or short-term guarantees, because you’re not going to be lying in the store for as long as you’re lying in bed at night. There’s no way to know how a mattress will perform over time,” she says. “Some places may let you try out a mattress for a month, and if you don’t like it, you can switch for a small fee.”

Spend sensibly

When it comes to mattresses, comfort is priceless, but the most expensive mattress isn’t always the coziest. “You don’t want to lose sleep over paying for a mattress,” Benjamin says. “You have to consider affordability. There’s quite a range of prices, so you have to consider this as an investment: Decide on what’s an acceptable price to pay and be comfortable with that, too.” After all, you don’t want anxiety over your mattress budget to keep you up at night.