Casper Waterproof Mattress Protector, King, White — breathable, quiet, fits up to 16" mattresses

The Casper Waterproof Mattress Protector (King, White) is a breathable, quiet, 360° stretch cover that shields your mattress from spills and stains without changing its feel.

Designed to disappear under your sheets, this protector combines a durable waterproof film with a soft, crinkle-free exterior and an engineered skirt that stays put. Casper developed the film after thermal and humidity testing to balance moisture protection with airflow, using materials similar to high-performance outdoor apparel. The result is a mattress cover that resists liquids, fits mattresses up to 16 inches deep, and remains comfortable night after night.

How does the protector keep liquids from reaching my mattress?

The protector uses an inner waterproof membrane that blocks spills, sweat, and everyday accidents while maintaining breathability. The film is laminated to soft fabric so it feels quiet and gentle under sheets, and tested for temperature neutrality so it won’t trap heat.

• Waterproof inner film prevents liquid penetration
• Breathable construction reduces heat buildup
• Crinkle-free outer layer for quiet sleep

Will it change the look or comfort of my mattress?

No—Casper designed this protector to preserve the original feel and appearance of your mattress. The surface is soft and unobtrusive, and the waterproof layer is thin enough that it won’t add firmness or alter pressure-relief characteristics.

• Soft fabric top keeps original mattress comfort
• Thin, advanced film avoids added stiffness
• White finish blends under most sheets for a seamless look

How does the fit and anti-shift design work on deep mattresses?

The protector features a full 360-degree skirt built from an active stretch material that grips corners and recovers shape to stay snug on mattresses up to 16 inches thick. Cross-directional stretch and machine-direction elastic let the fabric move with the mattress rather than popping off during regular use.

• Skirt stretches to accommodate up to 16" mattress depth
• Cross-directional stretch prevents bunching and slipping
• Clear head and foot labels make installation quick and correct

How do I care for the protector and keep it working long-term?

The protector is machine-washable and built to retain its protective qualities after routine laundering. Follow care instructions on the label: wash on a gentle cycle with mild detergent and tumble dry low or air-dry to preserve the waterproof film and elastic skirt.

• Machine washable—gentle cycle recommended
• Tumble dry low or air-dry to extend life
• Avoid bleach and fabric softeners that can degrade the film

Who is this for: The Casper Waterproof Mattress Protector is aimed at anyone who wants reliable, unobtrusive mattress protection—parents, pet owners, allergy-conscious sleepers, or anyone wanting to prolong a mattress’s lifespan without sacrificing comfort. It’s especially useful for deep mattresses up to 16 inches, buyers who prefer quiet, breathable materials, and households that need easy, machine-washable protection.