If you’re battling in your sleep over crucial snooze territory but don’t have the space for a king mattress, it’s time for you to consider the best California king mattresses. This less conventional mattress size falls between a queen and king in square footage and has a few extra inches of length (i.e., it’s a great bed for tall people). “Farther away from your partner (if you like that) means less heat, less breathing sounds, and less transmitted movement,” says Winter. While these sleep disturbances may not seem like a big deal, they can have serious short- and long-term impacts on your health1, including increased stress response, somatic issues, emotional distress, and memory and cognition issues, as well as an overall decrease in the quality of life. Surveys also show that people sleep better on bigger mattresses and generally feel less discomfort or joint pain during the night, per Winter. Plus, there’s simply more space for you and your partner—or your pets and kids—with a larger mattress. Ready to upgrade your sleep space? Scroll on to learn all about California king mattresses—and our favorite picks based on quality, sustainability, and customer reviews. Designed to accommodate side sleepers, it’s worth noting that some of the reviewers felt it didn’t offer enough cushioning. However, a cooling cover and reinforced sides still make this popular pick worth considering, especially for those needing a firmer option. While the gel-polymer-infused foam layer almost earned this mattress the top spot for keeping you cool, the layer of contouring transition foam ultimately landed this 12-inch pick a top spot for side sleepers. A greener pick than memory foam, latex also better holds its shape and is fully biodegradable—but it’s also pricey. A California king from Avocado will set you back nearly $4,000, but it’s a sound investment for those wanting to snooze in peace. Use the hidden inflator button to inflate (or deflate) the air chambers located in the top layer to reach the desired firmness. When paired with six layers of CertiPUR-US® certified foams, you get the ultimate oasis for snoozing. Plus, the split designs can even be used with an adjustable base for the ultimate customization. While memory foam isn’t the best for the environment, Casper has done everything possible to make sure it’s causing the least harm. This includes the fact that all foams are low VOC and CertiPUR-US® certified, which means that they don’t include any ozone-harming phthalates. While the brand doesn’t stand out on the sustainability front—you won’t find any special credentials listed on the site—it does have stellar customer reviews. If you’re not a fan, the 120-night trial will be a standout; if you are a fan, you’ll be grateful for the lifetime warranty. Better yet, it was also one of our standout picks for the best mattresses for hip pain and low-back pain. Optimal for side sleepers, it’s made with four layers of the foam, which retain their shape over time. And at 85 pounds, it’s also by far the lightest mattress option on this list. The hybrid option uses both memory foam and coils, which means it offers optimal motion isolation. Another perk? All foams are CertiPUR-US® and allowed time to air out in the factory, which limits off-gassing in your home. Both adaptive and supportive, it features a solid dense foam base layered with premium comfort foam under the grid. This gives a medium-firm feel with plenty of cushioning and pressure relief, although it has less support than the brand’s hybrid model. You’ll have 100 nights to decide whether the Plus is right for you, but if the reviews are any indication, you’ll also be impressed. More than 31,000 shoppers have reviewed this cooling mattress, yet it’s still earned a solid 4.4 out of 5 stars.