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Head-to-head · Best Cooling Pillows

Cozy Earth Mulberry Silk Pillow vs Slumber Cloud UltraCool Pillow

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

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The short answer

Cozy Earth Mulberry Silk Pillow and Slumber Cloud UltraCool Pillow score essentially the same (4.5 vs 4.5). Pick the one whose trade-offs match your priorities — the strengths and watch-outs below are where they actually differ.

Cozy Earth Mulberry Silk Pillow
Ranked #2 in Best Cooling Pillows
Cozy Earth Mulberry Silk Pillow
4 sources2 derived$158as of Aug 1

The Cozy Earth Silk Pillow is the luxury, naturally-cooling option in this lineup: 100% mulberry silk fill inside a premium bamboo viscose shell, with a 10-year warranty Cozy Earth backs against any defect. Cooling here is passive and gentle rather than aggressive, yet reviewers consistently rate it the most comfortable pillow they've ever tested. It suits hot sleepers who want a luxury bedding feel more than engineered cooling tech.

Strengths
  • — 100% long-strand mulberry silk fill — naturally breathable, hypoallergenic, and moisture-wicking
  • — Premium bamboo viscose shell stays cool to the touch and doesn't trap body heat
  • — Plush, weightless feel comparable to a down pillow without the allergens
Watch-outs
  • — Most expensive pillow on this list — $330 MSRP, often discounted to $200-264 on sale
  • — Cooling is passive rather than active; cool-touch sensation fades under a thick cotton pillowcase
  • — Cannot be machine-washed — silk fill is spot-clean and air-dry only
$158 · Buy at cozyearth.comFull review →
Slumber Cloud UltraCool Pillow
Ranked #3 in Best Cooling Pillows
Slumber Cloud UltraCool Pillow
3 sources1 derived$92.2as of Aug 1

The Slumber Cloud UltraCool Pillow puts Outlast phase-change fabric, the material Slumber Cloud built its bedding line on, into a soft down-alternative pillow. Apartment Therapy rated the adjustable version 4.5 out of 5, and Sleepopolis, reviewing the same Outlast fabric in Slumber Cloud's Nacreous cover, called it quite breathable and credited it with limiting heat retention overnight. The 30-night trial is the shortest here.

Strengths
  • — Outlast phase-change fabric absorbs and releases heat rather than just feeling cool at first touch
  • — Two firmness options and three sizes, including a 48-inch body pillow
  • — OEKO-TEX STANDARD 100 certified, with cover and fill both machine washable
Watch-outs
  • — The initial cool-touch sensation fades as the phase-change material saturates
  • — A 30-night trial is the shortest in this lineup
  • — Cooling is noticeably blunted by a thick pillowcase
$92.2 · Check Price on AmazonFull review →

Derived means the reviewer published no score, so one was inferred from their written verdict. Everything else is a number the publisher printed. How we rank.

How they stack up

Cozy Earth Mulberry Silk Pillow

The luxury counterpoint to everything else in this lineup. Where the Coop Cool+, Slumber Cloud UltraCool, and Purple Harmony are engineering-led approaches to cooling, the Cozy Earth is a materials-led approach — silk and bamboo just happen to be naturally cool. Doesn't compete with the Saatva Latex Pillow on warranty (Saatva's lifetime beats Cozy Earth's 10 years) but does compete on feel — both pillows aim for a plush, premium hand. Skip if you want pure cooling performance; pick if you want cooling alongside a luxury sleep experience.

Slumber Cloud UltraCool Pillow

It trades the adjustable loft of the Coop Cool+ for the Outlast fabric, which is the more proven temperature-regulating material in this category. It cools harder on contact than the Saatva Latex Pillow, though the Saatva's airflow story is more consistent in a hot bedroom, and it is roughly level with the Purple Harmony on temperature while feeling much softer.

Specs side-by-side

SpecCozy Earth Mulberry Silk PillowSlumber Cloud UltraCool Pillow
Material100% long-strand mulberry silk + bamboo viscoseDown-alternative polyester fiberfill
Fill100% AAA-grade mulberry silk floss100% polyester fiberfill (adjustable on Adjustable model)
Cover100% premium bamboo viscose shell100% polyester knit with Outlast coating
Cooling TechPassive — silk breathability + bamboo cool-touchOutlast phase-change material (NASA-derived)
SizesStandard, KingStandard 20x26, King 20x36, Body 20x48
Trial Period100 nights30 nights
Warranty10 years180 days
CareSpot clean, air dry onlyMachine wash cold, tumble dry low
Loft AdjustableNo — single fixed loftYes on Adjustable model; fixed on standard
CertificationsOEKO-TEX certifiedOEKO-TEX STANDARD 100
Loft OptionsSingle loft, ~5-6 inch—
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