Finally. A Mattress That
Doesn't Make You Sweat.
57% of adults sleep too hot. Here's what your mattress is doing wrong — and how Lull's cooling system keeps you comfortable all night.
By the Lull Sleep Team · Last updated: June 2026
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Why You Sleep Hot — The Science Brands Ignore
57% of US adults report regularly sleeping too hot — making temperature the most common sleep complaint after physical discomfort. If you've ever woken up sweating, thrown off the covers at 3am, or started the night comfortable only to overheat by morning, you're in the majority.
Your body has to follow specific temperature rules to fall — and stay — asleep. When your mattress traps heat, it disrupts that process, leading to restless nights, less deep sleep, and grogginess no matter how many hours you log. The good news: your mattress is the single most controllable variable in your sleep environment.
The Temperature Drop Requirement
Sleep onset requires your core body temperature to fall 1–3°F. Sleep scientists have identified the ideal bedroom temperature at 60–67°F for most adults — and your mattress is the surface your body spends 8 hours in direct contact with.
How Foam Traps Heat
Traditional memory foam is a dense, closed-cell material. As your body weight compresses it, foam cells close off and airflow stops. Body heat — which should dissipate into the sleep environment — instead builds up between you and the mattress.
The Real Sleep Cost
Sleeping hot causes more nighttime awakenings, less Stage 3 deep sleep, and reduced REM — the restorative cycles that determine how rested you feel. You can spend 8 hours in bed and still wake up exhausted when your body never fully cools down.
Sources: Gallup, AASM, Harding et al. (2019)
7 Features That Actually Keep You Cool
Not every cooling claim is equal. These are the seven features that make a measurable difference — and what to look for when comparing mattresses.
Gel-Bead Technology
Discrete heat-absorbing beads in the foam — not gel blended into cells. Beads actively capture and redirect body heat at a specific temperature threshold. Lull's proprietary approach.
✓ Lull has thisOpen-Cell Foam
Open-cell foam has a porous structure that lets air circulate through the material. Closed-cell foam traps air and heat inside. All Lull foam layers use open-cell construction.
✓ Lull has thisCoil Core Airflow
Hybrid mattresses with pocket coil cores have continuous airflow channels through the support layer. Heat escapes vertically and horizontally — not possible in all-foam designs.
✓ In Luxe modelsBreathable Cover
A stretch-knit cover lets air pass through to the comfort layers. Dense woven covers act as a heat seal at the surface. Look for open-weave or knit construction — Lull uses a hexagonal-tick knit.
✓ Lull has thisFirmness Level
Softer mattresses cause deeper body sinkage — compressing foam, reducing airflow, increasing contact area. Medium-firm typically sleeps cooler and is better for most hot sleepers.
Key considerationBreathable Mattress Protector
A sealed vinyl or dense polyester protector traps heat at the surface. Look for open-weave or terry-knit construction that lets air pass through while protecting against spills. Your protector shouldn't undo your mattress's cooling work.
✓ Lull protector breathesCooling Pillow
Your pillow traps as much heat as your mattress. Gel-infused or shredded foam pillows with breathable knit covers extend your cooling system from mattress to head. A hot pillow negates a cool mattress.
Key considerationHow the Luxe Premium Removes Heat — At Every Level
Every Lull mattress is built to move heat away from your body at multiple levels simultaneously. Here’s what’s happening inside the Luxe Premium Hybrid while you sleep.
01
The cover
Quilted Knit Cover Passes Heat Through, Not In
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The first point of contact between your body and the mattress. Lull uses a stretch-knit quilted cover — not a dense woven material that acts as a thermal seal. The open-weave structure lets body heat pass through to the cooling layers beneath rather than trapping it at the surface. Without a breathable cover, everything underneath it is compromised before it even starts.
02
Gel-bead comfort layer
Gel Beads Actively Capture and Redirect Heat
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Discrete cooling gel beads embedded in the memory foam — not blended gel, but separate particles that activate at a specific temperature threshold. When your body temperature rises, the beads absorb excess heat and redirect it away from your body. Active response, not passive absorption. The Luxe Premium uses a 2″ next-generation gel-bead layer with greater heat capture precision than standard gel foam.
03
Transition foam
Open-Cell Foam Lets Air Circulate Through the Stack
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The transition layer bridges the comfort foam above and the coil system below. Open-cell construction creates an interconnected porous structure that keeps air moving through the mattress rather than trapping it in sealed cells. It also limits sinkage depth — the less your body sinks in, the less contact surface area exists for heat to concentrate.
04
Comfort foam
Pressure Relief That Doesn’t Sacrifice Airflow
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A contouring foam layer that conforms to body shape for pressure relief at the hips and shoulders. Like every foam layer in the Luxe Premium, it uses open-cell construction — the same porous architecture that keeps airflow active throughout the stack. Comfort without the heat trap.
05
Pocket coil system
600+ Coils Create a Full-Mattress Airflow Highway
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The Luxe Premium’s 8″ foam-encased coil system contains 600+ individually wrapped pocket springs (Queen). Coils create continuous open channels through the entire support layer — heat escapes vertically and laterally, not just off the surface. This is the single biggest structural advantage a hybrid has over all-foam. NapLab independently scored this system 9.0/10 for cooling — above their 8.7 category average. Lull did not commission the test.
06
Base support foam
High-Density Foam Keeps the Coil Channels Open
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Below the coil system, a high-density support foam layer absorbs impact and prevents sag. Dense foam doesn’t compress under body weight the way softer materials do — which means the coil airflow channels above it stay open and functional through the night, not compressed into dead zones that would block heat from escaping.
07
Foundation panel
Reinforced Border Extends Cooling to Every Edge
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The foam-encased perimeter keeps each border coil individually wrapped rather than bonded in a rigid frame. This maintains airflow through the edges of the mattress while providing strong edge support. It also means the entire sleep surface stays usable — you’re not pushed toward the center where body heat from two people concentrates. Edge-to-edge cooling, not just center-of-mattress cooling.
Which Lull Mattress Is Best for Hot Sleepers?
All four Lull mattresses are built with cooling in mind — gel-bead foam, open-cell construction, and breathable covers throughout. The hybrid models add coil airflow for maximum heat dissipation.
The Original Lull
5 layers · All-foam · Gel-bead cooling
Best for: Budget-conscious back & stomach sleepers, mild hot sleepers
Lull's core cooling technology at the most accessible price. A 1.5" gel-bead comfort layer plus open-cell HR foam keep airflow moving throughout the night. The best all-foam cooling option for budget-conscious hot sleepers.
- 1.5" gel-bead viscoelastic comfort layer (ILD 13)
- Open-cell foam construction throughout all 5 layers
- Hexagonal-tick quilted breathable cover
- CertiPUR-US® certified · 365-night trial · Lifetime warranty
Original Premium
5 layers · All-foam · Thicker gel-bead layer
Best for: Side sleepers, hip & shoulder pressure, moderate hot sleepers
A 2" gel-bead layer (vs. 1.5" in the Original) means more cooling surface area and more gel beads working throughout the night. The medium-firm feel reduces sinkage depth, limiting contact-surface heat buildup — same open-cell construction, more cooling capacity.
- 2" gel-bead comfort layer — 33% thicker than Original
- Medium-firm feel limits sinkage for better airflow
- Open-cell foam throughout all 5 layers
- 365-night trial · Lifetime warranty · Free shipping
Luxe Hybrid
6 layers · Gel foam + 600+ pocket coils (Queen)
Best for: Hot sleepers, couples, combination sleepers, night sweats
Independently verified as the best-cooling mattress in the Lull lineup. The 8" pocket coil core (600+ coils, Queen) creates continuous airflow channels through the support layer. Gel foam captures surface heat.
- 2" cooling gel memory foam comfort layer (ILD 12)
- 8" pocket coil core — 600+ coils (Queen), continuous airflow
- 365-night trial · Lifetime warranty · Free shipping
Luxe Premium Hybrid
7 layers · Next-gen gel beads + foam-encased coils
Best for: Hot sleepers, heavier sleepers, luxury seekers, strong edge support
Upgrades the gel system to next-generation beads designed to capture and redirect heat with greater precision. The foam-encased coil system provides the same airflow advantage as the Luxe Hybrid, plus reinforced edge support. The pinnacle of the Lull lineup for hot sleepers who want no compromises.
- “Next-generation cooling gel beads capture heat and move it away”
- 8" foam-encased pocket coil system with reinforced edges
- 5-layer rayon-blend quilted & tufted premium cover
- 365-night trial · Lifetime warranty · Free shipping
Starting prices shown. View all sizes and prices →
Hot Sleeper Tips That Actually Work
Your mattress is the single biggest lever — but it doesn't work alone. These four changes will amplify your cooling mattress and help you stay comfortable all night.
Choose the Right Bedding
Best: 100% percale cotton, bamboo, or linen — breathable and moisture-wicking weaves. Avoid: sateen, polyester blends, and microfiber — they trap heat and feel clammy when damp. Thread count doesn't predict breathability; weave type does.
Set Your Room Temperature
The optimal bedroom temperature for sleep is 60–67°F. A ceiling fan running counterclockwise in summer creates a wind-chill effect that reduces perceived warmth by 4–6°F — no thermostat adjustment required.
Add a Breathable Mattress Protector
A breathable protector adds protection without heat — if you choose the right one. Look for: stretch-knit or Tencel surface with a TPU backing (waterproof but breathable). Avoid: vinyl or PVC backings, which trap heat at the surface.
Use a Cooling Pillow
Your head and neck generate significant heat during sleep. Dense foam pillows can be as problematic as a foam mattress. Look for: shredded latex or down-alternative fills with breathable cotton covers — or phase-change material pillow covers for severe hot sleepers.
Hot Sleepers Who Found Their Answer
From night sweats to couples with different sleep temperatures — Lull customers who sleep hot share their experience.
I used to wake up drenched at 3am every single night. My partner kept our old mattress — I switched to the Lull Luxe Hybrid. First week: zero night sweats. I genuinely could not believe how much of a difference the mattress made.
My husband runs hot and I run cold — a nightmare combo for mattress shopping. We've had the Luxe Hybrid for 6 months. He sleeps cooler, I stay warm enough with the duvet. First mattress we've both been happy on in 10 years of marriage.
As someone going through perimenopause, night sweats were destroying my sleep. My doctor told me to try cooling bedding — I went further and got a new mattress. The Lull Original Premium made a real, measurable difference. I'm sleeping through the night again.
Was skeptical about the gel beads claim — I've tried gel-infused foam before and it didn't help. The Luxe Hybrid is genuinely different. I wake up at the same temperature I went to sleep at. That's never happened on any mattress I've owned.
Bought this after reading the Sleep Foundation review. I live in Phoenix — it gets to 115°F in summer and I sleep with my AC at 72 because I run so hot. The Luxe Hybrid is the first mattress that doesn't feel like a heat trap. Life-changing is not an overstatement.
My wife and I both sleep hot. We tried a Purple, a Casper, and a Nectar before landing on the Lull Luxe Hybrid. The combination of the gel layer and the coils is the real deal — no more 3am cover-throwing. This is the one.
50,000+ reviews across all products · Read all reviews →
Frequently Asked Questions
Do gel memory foam mattresses sleep cool?
Not all gel memory foam sleeps equally cool. Traditional gel-infused foam mixes gel into the foam cells, absorbing heat passively. Lull uses discrete heat-dispersing gel beads that actively capture and redirect heat away from your body. Combined with open-cell foam construction, this creates a measurably cooler sleep surface than standard memory foam.
Is a hybrid or foam mattress better for hot sleepers?
Hybrids sleep cooler than all-foam mattresses for most hot sleepers. The coil core in a hybrid mattress creates continuous airflow channels through the mattress — heat can escape rather than build up. Lull's Luxe Hybrid earned a 9.0/10 cooling score from NapLab, with testers reporting no significant heat retention around the body.
What mattress do sleep experts recommend for hot sleepers?
Sleep experts generally recommend hybrid mattresses with gel-bead comfort layers, open-cell foam, and breathable covers for hot sleepers. The combination of coil airflow and gel cooling technology consistently outperforms all-foam options in independent testing.
Does the Lull mattress sleep cool?
Yes — independently tested by NapLab, the Lull Luxe Hybrid scored 9.0 out of 10 for cooling, above the 8.7 category average. The tester reported no significant heat retention. Lull's proprietary gel-bead technology actively disperses heat rather than absorbing it, and the pocket coil core provides continuous airflow throughout the mattress.
What temperature should a mattress sleep at?
Research shows your skin surface should stay between 33.5°C and 35.5°C (92–96°F) for optimal sleep. Your core body temperature needs to drop 1–3°F to initiate sleep onset. A mattress that traps heat elevates both skin and core temperatures, leading to more nighttime awakenings, less deep sleep, and grogginess even after a full night's rest.
Can a mattress help with night sweats?
A mattress can significantly reduce night sweating by dissipating body heat rather than trapping it. For people experiencing night sweats — from menopause, medications, or simply sleeping warm — a mattress with gel-bead cooling, open-cell foam, and a coil core provides passive temperature regulation throughout the night. Pairing with moisture-wicking bedding amplifies the effect.
What's the difference between gel-infused foam and gel-bead foam?
Gel-infused foam has gel material blended throughout the foam cells during manufacturing — it absorbs heat passively as it builds up. Gel-bead foam uses discrete beads of phase-change material that actively capture excess heat at a specific temperature threshold and redirect it away from your body. The bead approach is more targeted and more effective for sustained cooling throughout the night.
What firmness is best for hot sleepers?
Medium-firm mattresses typically sleep cooler than plush options. Softer mattresses allow deeper body sinkage, which compresses foam cells, reduces airflow, and creates more surface contact between your body and the mattress — all of which trap heat. A medium or medium-firm feel limits that sink-in effect while still providing adequate pressure relief for most sleep positions.
Sources: NapLab Luxe Hybrid cooling test; Harding et al., "Thermoregulation and Sleep," 2019; American Academy of Sleep Medicine.
9.0/10 Cooling · Sleep Foundation Pick · 365-Night Trial
Sleep cool. Starting tonight.
Independently tested. Expert-cited. 365 nights to find out if Lull is your answer to sleeping hot — or your money back.
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