The cover is the very first bit of your mattress you come into contact with, but it's often overlooked because it's hidden beneath your sheets. However, the cover of a mattress plays a bigger role in helping you achieve restful sleep than you may think. As a professional mattress tester who's slept on a wide range of materials, I’m here to explain why you should care what these covers are made from.
During a recent 3Z Brands factory tour in Arizona with the Tom's Guide sleep team I gained insight into the range of materials used for mattress covers, from polyblends and organic fibers to proprietary cooling fabrics designed to wick away heat and moisture. All of this year's best mattresses that we've tested use a cover that works in harmony with the comfort and support layers to provide restorative, comfortable sleep.
Familiarize yourself with the types of materials mattress covers are made from before browsing this month's best mattress sales, then go forth to find a bed you can't wait to fall into every night.
What is a mattress cover?
A mattress cover is the top layer of a mattress. It wraps around the internal layers of the mattress to keep them intact and protect them from damage. The cover is usually fixed to the mattress, although some models feature removable covers that you may also be able to launder.
The most common materials used for mattress covers are polyester, cotton, wool, Tencel, and cashmere. Cooling mattresses feature specialist materials designed to wick away heat and moisture while providing a soothing sensation upon touch.
5 common mattress cover fabrics
1. Polyester
Polyester is a synthetic material that's durable, moisture-wicking, and affordable — which is why it's usually found in the covers of the best cheap mattresses.
However, polyester isn't too breathable on its own, so in mid-range mattresses it's typically blended with natural fibers like cotton or wool. Some brands may use polyester with polyethylene or phase change materials to create a cooling effect.
2. Cotton
Cotton is a natural plant fiber widely used in luxury and organic mattresses because of its breathability, durability, and softness. It's either used on its own or blended with polyester or other natural materials.
Although cotton is a natural fiber, it is not always organic. To determine if the cotton in a mattress cover is organic, look for mattress certifications such as those from the Global Organic Textile Standard (GOTS) or OEKO-TEX (OEKO-TEX Organic Cotton).
3. Wool
Wool is a natural fiber primarily used in organic or luxury mattresses. Made from the fleece of sheep, it's cozy and regulates temperature well, keeping you warm in the winter and cool in the summer. However, wool can be expensive, especially if it's certified organic and sustainably sourced.
Beyond mattress covers, wool is often used as an alternative to fiberglass, a common fire retardant in lower-cost mattresses. (Fiberglass may pose health risks when exposed, which is why the covers on such mattresses aren't meant to be removed.)
4. Tencel
Tencel is a semi-synthetic cellulose fiber derived from wood pulp, usually eucalyptus. Like cotton, Tencel is breathable, durable, and soft. While it's not a totally natural fiber, Tencel is considered more eco-friendly than cotton because it requires less water during production. (It's also less prone to wrinkling than cotton.)
5. Cashmere
Cashmere is a type of wool that's derived from the fine hairs of goats. It's soft, lightweight, and luxurious. It's also delicate, although cashmere may be blended with other fibers to make it more durable (and affordable).
3 types of cooling mattress cover materials
1. GlacioTex
GlacioTex is a proprietary material developed by Helix Sleep. It's a 50/50 blend of polyester and polyethylene (a type of thermoplastic), resulting in a smooth surface that's cool to the touch. The high thermal conductivity of GlacioTex fibers draws heat away from your body as you sleep.
Today, GlacioTex is featured in the covers of cooling mattresses from Brooklyn Bedding and Nolah — which, along with Helix Sleep, are part of 3Z Brands.
2. Celliant
Developed by materials science company Hologenix, Celliant uses thermo-reactive minerals and 88 trace elements to convert your body heat into infrared energy. It then reflects that energy back into your body to improve thermoregulation, cell oxygenation, and blood circulation. It's also moisture-wicking and fast-drying.
Celliant is marketed towards athletes and those with active lifestyles as it promises higher performance through restorative sleep. It's primarily featured in Bear mattresses.
3. 37.5 Technology
37.5 Technology works similarly to Celliant by absorbing your body's infrared energy. It's made from porous volcanic minerals and coconut-derived activated carbon, which the brand claims allows the fabric to evaporate moisture at the vapor stage, preventing you from waking up in a sweat.
Right now, 37.5 Technology is mostly used for bedding and apparel, but there are a handful of sleep brands that use this specialty fabric for their mattress covers.
4. Phase change material
Phase change material (or PCM) functions similarly to an ice pack. When exposed to your body heat it melts, creating a cooling sensation upon contact. At the same time, it absorbs that heat to maintain a comfortable sleeping temperature.
Unlike the materials above, phase change material is not proprietary. Brands like Cocoon by Sealy and Bear weave PCM into yarns to create cooling mattress covers. Some even use PCM-infused memory foam for enhanced temperature regulation, such as Casper's Snow mattresses.
Mattress cover FAQs
What is mattress ticking?
Mattress ticking refers to the outermost layer of the mattress (the cover). Among mattresses-in-a-box, the two common types of ticking are knitted covers and damask covers.
Knitted covers are more flexible, and in higher-end mattresses, they may include tufting or quilting for added comfort and luxury. Damask covers are woven, offering better breathability and often featuring decorative patterns.
There's also special-type mattress ticking, which includes proprietary cooling covers and fabrics treated with antimicrobials.
Can you wash a mattress cover?
In most cases, mattress covers are not removable so you'll have to spot-treat any stains or spills. (Also make sure you're using a mattress protector.)
That said, even if a mattress cover is removable, that doesn't mean you can wash it. If you remove a mattress cover that's meant to be left intact, you could be at risk of fiberglass exposure, which will not only be time-consuming to clean up, but also irritate your skin, eyes, and lungs.
Of course, you'll want to abide by the manufacturer label — and if it says it's safe to wash, then do so according to the guidelines.
Do cooling mattress covers really work?
Cooling mattress materials will vary in efficacy from one sleeper to the next, but if you or your partner are prone to overheating at night, it may be worth the investment. At the very least, you'll want to avoid mattresses with materials that aren't very breathable on their own, like polyester and dense memory foam.