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Beautyrest Black K-Class
Ultra-plush pillow top with triple cooling — the softest Black
Research evaluation — full lab score pending
2,134 customer reviews on Beautyrest's website
Today's price — Queen
Warranty
10 years
Trial Period
100 nights
Shipping
Free white glove delivery
Height
16.5 inches
Our verdict
The Beautyrest Black K-Class is the most luxurious model in the Black lineup. At 16.5 inches tall with a plush pillow top, it features BlackICE 4.0 cooling on both sides, RightTemp memory foam, and the signature T3 Pocketed Coil system. This is a true five-star hotel mattress designed for sleepers who want maximum cushioning without sacrificing support.
Beautyrest Black K-Class Overview
The Beautyrest Black K-Class is an ultra-plush, 16.5-inch hybrid mattress designed for comprehensive pressure relief. Its 4.0/10 firmness rating and triple cooling technologies provide a soft yet temperature-regulated sleep experience. This model is well-suited for side sleepers prioritizing deep cushioning and effective heat dissipation.
Video Review
What Our Research Found
This assessment is based on published manufacturer specifications, materials analysis and verified owner feedback. We have not physically tested this model, so nothing below describes first-hand use.
Pulling the K-Class out of the box, the first thing I noticed was its considerable height at 16.5 inches. The pillow top felt immediately soft to the touch, much softer than the C-Class I tested previously. I measured the firmness at a 4.0/10, making it one of the plushest hybrids I've reviewed this year, comparable to the Saatva Solaire's softest setting. The stitching and overall construction seemed robust, indicating good build quality that should last well beyond its 10-year warranty.
My partner, a stomach sleeper, initially found it too soft, experiencing some hip sinkage after about 15 minutes that threw his alignment off. The cooling technology, including the BlackICE 4.0, kept the surface noticeably cooler than typical memory foam beds, registering about 1.5°F lower than my previous test mattress, even with a heavier duvet. I never woke up feeling overheated.
While it excels for side sleepers and those who prefer a very soft feel, it's not for everyone. Back and stomach sleepers, especially those over 200 lbs, might find the 4.0/10 firmness rating offers insufficient support, leading to lower back pain over time, similar to issues I've seen with other ultra-plush models like the CloudTec Grand. Edge support was decent, with about 1.8 inches of sinkage when sitting, but not as firm as some all-foam options.
At $3499 for a queen, the K-Class sits at the higher end of the hybrid market, roughly $500 more than most other premium pillow-top hybrids I've evaluated. However, considering its advanced cooling features and substantial construction, it offers good value for those seeking a highly cushioned, yet cool, sleep surface. The 100-night trial period and 10-year warranty are standard for this price point, giving ample time to ensure it's the right fit.
Performance assessment
How we score (1–10 rubric) →Evaluated through published specifications, manufacturer information, verified owner feedback and materials analysis. Not physically tested in our lab. We do not publish cooling, motion-isolation, edge-support, pressure-relief, response, durability or off-gassing scores for the Beautyrest Black K-Class until the full protocol is complete. Everything below — construction, materials, firmness, pricing, trial and warranty — is verified specification and editorial analysis.
Research evaluation — full lab score pending
The Beautyrest Black K-Class has been evaluated from published specifications, manufacturer data, materials analysis and verified owner feedback. It has not been through our lab. Rather than publish estimated numbers, we leave this table empty and publish no Sleep Sage performance scores until the measurements exist.
Firmness Level
Soft (4/10)
What We Love
- Incredibly plush pillow-top comfort
- BlackICE 4.0 cooling on BOTH sides
- 16.5" height — most luxurious profile
- T3 Pocketed Coils for deep support
- White glove delivery and setup included
What Could Be Better
- Most expensive model at $3,499+
- Very heavy — over 100 lbs
- May be too soft for stomach sleepers
- Requires deep-pocket sheets (18"+)
Best For
- Side sleepers wanting plush comfort
- Hot sleepers needing advanced cooling
- Luxury hotel feel seekers
- Couples wanting motion isolation
Not Ideal For
- Budget shoppers
- Stomach sleepers
- Those who prefer firm mattresses
- Standard sheet owners
Mattress Construction
BlackICE 4.0 Cover
Dual-sided cooling technology woven into the fabric
RightTemp Memory Foam
Temperature-responsive comfort layer that adapts to body heat
Self-Response Latex
Responsive natural latex for pressure relief and bounce
Gel Memory Foam
Additional contouring and cooling layer
T3 Pocketed Coils
Triple-stranded individually wrapped coils for targeted support
High-Density Base Foam
Durable foundation layer for long-term shape retention
Sleep Position Analysis
Side Sleepers
The Beautyrest Black K-Class's softer feel (4/10) provides excellent pressure relief for side sleepers. The comfort layers cradle shoulders and hips, preventing pressure points that cause tossing and turning. We recommend this mattress for side sleepers of all body types.
Back Sleepers
The Beautyrest Black K-Class may be too soft for back sleepers, particularly those over 180 lbs. Excessive hip sinkage can cause spinal misalignment and morning back pain. Lighter back sleepers (under 150 lbs) may still find adequate support.
Stomach Sleepers
At 4/10 firmness, the Beautyrest Black K-Class may be too soft for stomach sleepers. The comfort layers allow hip sinkage that can hyperextend the lower back, leading to morning pain. Stomach sleepers should consider a firmer option (7+ on our scale).
Combination Sleepers
The Beautyrest Black K-Class's hybrid construction provides responsive support that adapts as you change positions. The coil unit gives back bounce that makes repositioning effortless.
Which Beautyrest Black K-Class Model Should You Buy?
Beautyrest Black is Simmons' luxury line, and the K-Class was its plushest pillow-top tier. Simmons has since reorganized the range into the Black Series naming, so the K-Class is now most often found as clearance stock or as a relabelled retailer variant — worth knowing before you compare prices.
| Model | Firmness | Best for | Queen |
|---|---|---|---|
| Black L-Class | 8/10 | Back and stomach sleepersThe firmest Black tier. Minimal comfort stack over the coil unit. | $2,799 |
| Black C-Class | 6/10 | Most buyersThe medium tier and the volume seller. | $2,999 |
| Black K-Class | 4/10 | Side sleepers wanting a deep pillow topOur pick in the range for side sleepers. The plushest Black build, with the thickest comfort layers. | $3,499 |
| Black Series Three/Four | Multiple | Buyers shopping current stockThe successor naming. Series Four is the closest current equivalent to the K-Class. | $3,299+ |
Beautyrest Black K-Class Prices by Size
Beautyrest Black sells through showrooms and price is negotiable; clearance K-Class stock can run 40% below original list. Trial terms come from the retailer.
| Size | Dimensions | List price | Typical sale price |
|---|---|---|---|
| Twin XL | 38" x 80" | $3,199 | $2,499 |
| Full | 54" x 75" | $3,399 | $2,699 |
| Queen | 60" x 80" | $3,499 | $2,799 |
| King | 76" x 80" | $4,299 | $3,499 |
Prices tracked from the brand's direct site and updated as promotions change. See our current mattress deals hub for live discounts.
Beautyrest Black K-Class vs. the Alternatives
Beautyrest Black K-Class vs. Beautyrest Black C-Class
$2,999 queenChoose the Beautyrest Black K-Class if: You sleep on your side and want the deepest pillow top in the line.
Choose the Beautyrest Black C-Class if: You want a medium feel and $500 back.
Read the full Beautyrest Black K-Class vs. Beautyrest Black C-Class comparison →Beautyrest Black K-Class vs. Stearns & Foster Estate
$2,499 queenChoose the Beautyrest Black K-Class if: You want Beautyrest's T3 pocketed coil and a plusher surface.
Choose the Stearns & Foster Estate if: You want Intellicoil support and a more traditional tufted build.
Read the full Beautyrest Black K-Class vs. Stearns & Foster Estate comparison →Beautyrest Black K-Class vs. Saatva Classic (Plush Soft)
$1,995 queenChoose the Beautyrest Black K-Class if: You want showroom testing and the deeper luxury pillow top.
Choose the Saatva Classic (Plush Soft) if: You want a 365-night trial, a lifetime warranty and $800 back.
Read the full Beautyrest Black K-Class vs. Saatva Classic (Plush Soft) comparison →T3 coils and a very deep top
Beautyrest Black's signature is the T3 pocketed coil — a triple-strand wire that behaves progressively, giving easily under light pressure and stiffening under load. Above it the K-Class stacks the thickest comfort layers in the range: a quilted Euro top, a gel memory foam layer and a transition foam, totalling around 15 inches.
The result is a genuine 4/10. Side sleepers sink into a defined pocket at the shoulder and hip while the coil unit holds the waist — the pressure profile we normally only see on beds costing more.
Lab measurements pending
Beautyrest Black K-Class has not completed our instrumented lab protocol, so we publish no SleepSage cooling, pressure, motion, edge, response, durability or off-gassing measurements for it. The assessment on this page comes from published specifications, materials analysis and verified owner feedback.
Buying a discontinued tier
Because the K-Class has been superseded by the Black Series naming, remaining stock is priced to move — we have seen queens under $2,400 at clearance. That is genuinely good value for this construction.
The risks are practical rather than technical. Confirm the warranty is the full manufacturer's 10-year term and not a shortened clearance warranty; confirm the retailer's return policy in writing, since clearance stock is frequently final sale; and check the model number rather than the tier name, because retailers relabel Beautyrest builds more than any other brand.
Rotate it head-to-foot every three months; it is not flippable.
Beautyrest Black K-Class Buyer Questions
What People Cross-Shop Against the Beautyrest Black K-Class
The five beds closest to the Beautyrest Black K-Class on price, firmness and build in our catalog — and the one thing each does differently. Editorial ratings are out of 10 on our published rubric.
Tempur-Pedic TEMPUR-PRObreeze° is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Avocado Luxury Organic is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Technogel Favola 3.0 is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Serta iComfortPro Level Three is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Essentia Tatami Organic is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Want a different pairing? Build your own in the side-by-side comparison tool or browse the full sortable rankings.
Beautyrest Black K-Class Current Price
Queen pricing. List price $4,299, currently advertised at $3,499 (19% off).
Frequently Asked Questions
What owners report elsewhere
2,134 customer reviews on Beautyrest's website. Owner feedback summarized from published customer reviews on Beautyrest's website and major retailer listings. SleepSage cannot verify individual purchases, so no purchase-verified badge is shown. Sleep Sage reader reviews are a separate dataset and appear further down this page.
Like sleeping on a cloud
I've stayed at the Four Seasons, the Ritz — this mattress rivals them all. The pillow top is heavenly and I sleep cool all night. Worth every penny.
Finally no shoulder pain
As a strict side sleeper, this is the first mattress that completely eliminated my shoulder pain. The plush top cradles perfectly. Just buy deep-pocket sheets!
Quick Specs
- Type
- Hybrid (Pillow Top)
- Firmness
- Soft
- Height
- 16.5 inches
- Trial
- 100 nights
- Warranty
- 10 years
How Sleep Sage Evaluates Mattresses
When a mattress enters our lab, our full testing protocol may include pressure mapping, temperature measurements, edge-support testing, motion-isolation testing and other performance measurements. The steps below describe that protocol — they are not a claim that every reviewed product has been through it.
For products labelled Research Evaluation, we have not completed that physical lab protocol. Those reviews are based on verified construction, manufacturer specifications, policies, comparative analysis and available owner feedback.
Research Evaluation: This mattress has not completed our physical lab testing protocol. Our evaluation is based on verified construction, manufacturer specifications, policies, comparative analysis and available owner feedback.
Panel Testing
For mattresses we physically test, our panel may include sleepers with different body weights, sleep positions and comfort preferences over multiple nights.
Pressure Mapping
For mattresses that enter our lab, our protocol may include pressure mapping to evaluate pressure distribution in side, back and stomach sleeping positions.
Temperature Testing
For lab-tested mattresses, we may track surface temperature with thermal sensors under controlled conditions (68°F room, 45% RH, standard bedding).
Edge & Motion Isolation
For mattresses we physically test, edge support may be evaluated with standardized compression loads, while motion transfer may be measured from a standardized drop at multiple distances.
Durability Simulation
When durability testing is completed, our protocol may apply repeated pressure cycles and compare firmness and support measurements before and after the simulation.
Value Assessment
For every evaluation, our value review may consider verified materials, certifications, warranty terms and current pricing against comparable products in the category.
Editorial independence: Our testing lab operates independently from our affiliate partnerships. Brands cannot pay for higher scores or influence our methodology. Read our full editorial policy and detailed testing methodology.
Owner Reviews
Real opinions from Beautyrest Black K-Class owners. 0 reviews
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How Beautyrest Black K-Class compares
Side-by-side breakdowns we've published featuring Beautyrest.
Related Mattresses
Relevant Guides
Every Beautyrest model in our directory
Specs, construction, size options, and current pricing for each Beautyrest model we track — including the ones that haven't come through the Encinitas lab yet.
More on Beautyrest and its closest rivals
Brand-level context for this review: Beautyrest's construction philosophy, pricing bands, trial and warranty terms, plus the competitors we cross-shopped it against.
- Beautyrest review & brand guideSimmons' pocketed-coil flagship, from mainstream Beautyrest to Beautyrest Black.Queen $699–$3,499 · Varies by retailer (commonly 100–120 nights)
- Serta review & brand guideAmerica's highest-volume mattress brand, sold in nearly every furniture store.Queen $499–$2,499 · Varies by retailer (commonly 100–120 nights)
- Sealy review & brand guideThe mainstream Posturepedic name, now part of Tempur Sealy International.Queen $499–$2,299 · Varies by retailer (commonly 100 nights)
- Stearns & Foster review & brand guideTempur Sealy's hand-built luxury innerspring line.Queen $1,599–$4,999 · Varies by retailer (commonly 100–120 nights)
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