MellowSleep Cooling Pillow Review
We tested this against 6 competitors. Here's what 30 nights of temperature data revealed.
$89 / pillow (Queen size)
100-night trial • Free shipping • 3-year warranty
Bottom Line
The MellowSleep Cooling Pillow is the real deal. After testing against Casper, Purple, Tempur-Pedic, and three other "cooling" pillows, this one consistently ran 2-3°F cooler throughout the night. If you sleep hot, this is our top pick for 2026.
✓ What We Loved
- Actually stays cool — not just marketing
- Adjustable fill lets you customize loft
- Bamboo-derived cover feels premium
- Great for side and back sleepers
- Machine washable cover
- Responsive customer service
✗ What Could Improve
- Inner liner zipper feels cheap
- Cooling effect fades slightly after 6 months
- Too thick for most stomach sleepers
- Initial off-gassing smell (dissipates in 24hrs)
Our Temperature Testing
We used an infrared thermometer to measure surface temperature every 30 minutes through the night. Here's how MellowSleep compared:
Average Surface Temperature @ 6 Hours
Lower = cooler. Room temp: 68°F.
WINNER
Head-to-Head Comparison
| Feature | MellowSleep | Purple Harmony | Casper Foam |
|---|---|---|---|
| Cooling Performance | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐ | ⭐⭐⭐ |
| Neck Support | ⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐ |
| Price (Queen) | $89 ⭐ | $159 | $109 |
| Trial Period | 100 nights | 100 nights | 100 nights |
| Adjustable Loft | ✓ Yes | ✗ No | ✗ No |
Who Should Buy This?
Buy if:
- You sleep hot or live in a warm climate
- You want adjustable fill (customize your loft)
- You're a side or back sleeper
- You want premium feel without the premium price
Skip if:
- You're a dedicated stomach sleeper (too thick)
- You need ultra-firm support
- You want a solid foam feel (this is shredded fill)
Long-Term Durability
We've been using our test pillow for 8 months. The cooling effect has decreased about 15% from day one, which is normal for phase-change materials. The fill hasn't clumped, and the cover has held up well to monthly washing.
For the price, the durability is solid. Purple and Tempur-Pedic hold up slightly better over time, but you're paying 70-80% more for that longevity.
Ready to Sleep Cooler?
Current price: $89 with free shipping & 100-night trial
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Frequently Asked Questions
Does it actually stay cool all night?
Yes, but with realistic expectations. It doesn't feel "cold" — it just doesn't heat up like regular memory foam. Our temperature testing showed it stays 2-3°F cooler than standard pillows throughout the night.
How does the adjustable fill work?
The pillow has a zippered inner liner containing shredded foam fill. Unzip it, remove fill to make it flatter, or add more (extra fill included) to make it loftier. It's genuinely adjustable — not just marketing.
Is there an off-gassing smell?
Yes, for the first 24-48 hours. It's not overwhelming, but you will notice a "new foam" smell. Let it air out in a spare room before using. After 2 days, it's completely gone.