CoolNest® Ultra Memory Foam Mattress

All four CoolNest® mattresses are designed to deliver cooler sleep, but each offers a different balance of cooling, support, and comfort.

• CoolNest® Memory Foam Mattress – Best value option with cooling comfort, pressure relief, and 5-zone ergonomic support.
• CoolNest® Pro Memory Foam Mattress – Upgraded all-foam model with 4-stage cooling, triple-perforated foam, and 7-zone precision support.
• CoolNest® Ultra Memory Foam Mattress – Premium cooling model featuring the Advanced CoolNest® Ultra System, PCMflux® foam, AirMesh™ foam, and 5-stage cooling technology.
• CoolNest® Hybrid Mattress – Combines cooling foam with individually pocketed coils for enhanced support, responsiveness, and edge stability.

Which one should you choose?

• Choose CoolNest® if you are new to cooling mattresses and want essential cooling comfort at a budget-friendly price.
• Choose CoolNest® Pro if you are a hot sleeper looking for stronger, longer-lasting cooling with enhanced comfort.
• Choose CoolNest® Ultra if you prioritize premium cooling, restorative sleep, and overall well-being.
• Choose CoolNest® Hybrid if you are a back or combination sleeper looking for enhanced support and the responsive feel of a hybrid mattress.

Learn more about CoolNest vs Pro vs Ultra vs Hybrid: Which One Is Actually for You?

The CoolNest® Ultra is best for sleepers who prioritize advanced cooling, pressure relief, and premium comfort. It is especially well suited for hot sleepers, side sleepers, back sleepers, and couples who want a cooler sleep surface, targeted support, and excellent motion isolation.With its 5-stage cooling system, PCMflux® foam, AirMesh™ breathable foam, and 7-zone support design, the CoolNest® Ultra is a great choice for those looking for a more restorative sleep experience with enhanced temperature regulation and full-body support.

Yes. The CoolNest® Ultra combines strong motion isolation, advanced cooling, and targeted support, making it a great option for couples. The all-foam design helps absorb movement so you're less likely to feel a partner tossing and turning, while the cooling system helps reduce heat buildup that can occur when two people share a bed.

Yes. The CoolNest® Ultra is designed to provide the balanced support that most back sleepers need. Its 7-zone ergonomic support system helps support the lower back and hips while maintaining healthy spinal alignment. For back sleepers, the 12-inch and 14-inch models offer the best combination of contouring comfort and stable support.

Yes. The CoolNest® Ultra is an excellent choice for side sleepers thanks to its pressure-relieving memory foam and 7-zone support system. The comfort layers help cushion the shoulders and hips, while targeted support zones promote proper spinal alignment and reduce pressure buildup throughout the night. The 14-inch and 16-inch models are especially well suited to side sleepers who prefer a more plush, cradling feel.

Yes — cooling is the reason the Ultra exists. The gradient ice silk cover (Qmax 0.25) feels cool the moment you lie down and wicks moisture off the surface. Beneath it, PCMflux® phase-change foam absorbs excess heat as your body warms and releases it as you cool, which flattens out the temperature swings that wake people up sweating. AirMesh™ foam and the 3D open-channel structure then vent that heat out of the mattress rather than letting it pool. It's the coolest mattress SweetNight makes.

Yes — cooling is the reason the Ultra exists. The Gradient Ice Silk Cover (Qmax 0.25) feels cool the moment you lie down and helps wick away heat and moisture from the surface. Beneath it, PCMflux® phase-change foam absorbs excess heat as your body warms and releases it as you cool, helping maintain a more consistent sleep temperature throughout the night. A ventilated gel memory foam layer with precision airflow channels further enhances airflow and heat dissipation, while AirMesh™ breathable memory foam and the 3D Open-Channel Breathable Structure continuously carry trapped heat away from the mattress to deliver a cooler, fresher sleep experience.

The CoolNest® Ultra uses an upgraded 5-stage cooling system to move heat away from your body and release it through the mattress. The Gradient Cooling Ice Silk Cover provides instant cooling, while PCMflux® foam absorbs and regulates excess heat. AirMesh™ breathable foam, ventilated gel foam, and the 3D open-channel structure then promote continuous airflow and heat dissipation throughout the night. Together, these layers help the mattress feel up to 11° cooler than traditional memory foam. Learn more about How Does a Mattress Sleep 11 Degrees Cooler?

All three CoolNest® Ultra models feature the same advanced cooling system and 7-zone support design, but each offers a different feel:

• 12" Medium – Best for sleepers who prefer a more balanced, supportive feel.
• 14" Medium Plush – Offers a blend of contouring comfort and support, making it a great fit for most sleep positions.
• 16" Medium Plush – Provides the deepest cushioning and pressure relief, making it ideal for side sleepers and those who prefer a softer, more cradling feel.

Most sleepers will be happy with the 14" model, while side sleepers and those seeking maximum plush comfort may prefer the 16" model.

The CoolNest® Ultra is available in Queen and King sizes, with a choice of 12-inch, 14-inch, and 16-inch profiles. Each profile features the same Advanced CoolNest® Ultra cooling technologies and 7-zone support system, while offering a different balance of comfort, pressure relief, and cushioning.

The CoolNest® Ultra is backed by a 10-year limited warranty and a 100-night sleep trial.

The Sleep Foundation Test Lab evaluated the Sweetnight CoolNest Ultra Mattress and praised its motion isolation (9.5/10) and pressure relief (9.0/10), making it an excellent choice for couples and side sleepers seeking targeted zoned support.

Sleep Doctor's product testing team tested all three CoolNest® Ultra heights and rated the mattress 8.4 out of 10 overall. It earned a perfect 10/10 for motion isolation, which their reviewers called "among the strongest we've seen," noting that the foam layers "absorb nearly all vibrations big and small." Pressure relief scored 9.5/10 and appears in their listed pros as "superior pressure relief well-suited to side sleepers," alongside "zoned support to promote better posture." The review is equally clear about the trade-offs of an all-foam build: perimeter support scored 6.0 and temperature control 6.5, and their own tip for hot sleepers is to choose the firmer 12" profile, since less sinkage means the surface traps less heat. The review was written by Garen Glazier and reviewed by Michael J. Breus, PhD.

NapLab independently tested the SweetNight CoolNest Ultra Mattress and rated it 8.50 out of 10 overall. Their evaluation highlighted strong performance in response time (9.7/10), pressure relief (9.0/10), and company policies (9.0/10), along with solid scores for motion transfer (8.8/10) and cooling performance (8.0/10). NapLab found that the CoolNest Ultra provides significant contouring and pressure relief with its memory foam construction, making it a suitable option for sleepers who prefer a traditional foam feel. Their testing also showed that the mattress offers good motion isolation and a fast material response time compared with many memory foam mattresses.

Yes. The CoolNest® Ultra has been featured in New Atlas (August 2026) and TechWalls. Both are sponsored placements rather than independent tests, and they document the 5-stage cooling build in detail: a Gradient Cooling Ice Silk Cover rated at Qmax 0.25 J/(cm²·s) with over 10,000 micropores per square centimetre, PCMflux® High Resilience Foam carrying twice the phase-change material and gel particles of traditional formulations, a ventilated gel memory foam layer with 30% gel particles and more than 700 ventilation openings, AirMesh™ Breathable Memory Foam offering up to six times the breathability of traditional closed-cell memory foam, and a wave-shaped open-channel support structure over a high-density base. Independent scoring comes separately from Sleep Doctor's product testing team.

The CoolNest® Ultra is engineered to feel up to 11° cooler than a traditional memory foam mattress. Powered by the Advanced CoolNest® Ultra System, its 5-Stage Cooling Design combines a Gradient Ice Silk Cover with a Qmax of 0.25 J/(cm²·s) for an instant cool-to-the-touch feel, PCMflux® high-resilience foam that absorbs and releases heat as your body temperature changes throughout the night, AirMesh™ breathable memory foam, a ventilated gel memory foam layer, and a 3D open-channel breathable structure that promotes continuous airflow and carries trapped heat away from the mattress for cooler, fresher sleep.

AirMesh™ Breathable Memory Foam is SweetNight's proprietary open-channel breathable memory foam, engineered to deliver up to 6× greater breathability than traditional memory foam. It promotes continuous airflow and faster heat dissipation while maintaining the adaptive contouring and pressure-relieving comfort of premium memory foam. As a key layer of the Advanced CoolNest® Ultra System, it helps keep your sleep cooler and fresher throughout the night.

The CoolNest® Ultra is available in two comfort levels depending on mattress height: the 12-inch model offers a Medium feel, while the 14-inch and 16-inch models provide a Medium Plush feel. The thicker models feature a more cushioned comfort surface paired with a thicker high-density support foam base, delivering enhanced pressure relief while maintaining stable, full-body support. Combined with the 7-zone contour-cut support design, each model helps promote proper spinal alignment and balanced comfort. The 12-inch model is ideal for sleepers who prefer a more balanced feel, while the 14-inch and 16-inch options are better suited to side sleepers or anyone seeking a softer, more cradling sleep experience without excessive sinking.

Not yet — the CoolNest® Ultra currently comes in Queen and King, in 12", 14", and 16" thicknesses. Twin and Full are joining the lineup November, 2026 and are expected to be available in time for our Black Friday mattress sale, so if you can wait, that's the moment to buy. Join the waitlist and we'll email you the day they go live, along with early access to Black Friday pricing. If you need a Twin, Twin XL, Full, or California King sooner, the CoolNest® Memory Foam Mattress is available in those sizes today and delivers the signature CoolNest® cooling comfort at a more accessible price.

The CoolNest® Ultra is backed by trusted certifications. All foams are CertiPUR-US® certified, meaning they're made without ozone depleters, heavy metals, formaldehyde, or prohibited phthalates, and are tested for low VOC emissions. The Gradient Ice Silk Cover is OEKO-TEX® STANDARD 100 certified, with every component tested for substances harmful to skin. The mattress is also recognized by the American Chiropractic Association (ACA) for its ergonomic support and sleep-focused design.

Yes. Sleep on the CoolNest® Ultra for 100 nights. If it isn't right, contact us for free pickup and a full refund — no return shipping cost. We do recommend giving it at least 30 nights, since it takes most people a few weeks to adjust to a new support system. Returned mattresses are donated to local charities. The Ultra also includes a 10-year warranty covering sagging over 1.5 inches.