Best Serta King Mattresses in 2026: 4 Picks

Quick picks

The best fit for you

• You need firm support for your lower back Serta Sleeptrue Firm 12" King The 12-inch firm design targets lower back alignment with gel memory foam.
• You are a side sleeper needing plush comfort Serta Perfect Sleeper Ultimate 13.25" Plush King This 13.3-inch plush model contours to your body while offering edge support.
• You prefer a medium feel with cooling gel Serta 10" Cooling Gel Memory Foam King The cooling gel cover and medium foam construction help regulate temperature for airflow.
• You want the most compact model on the list Serta Five Star Tranquility 10" King At 10 inches tall, this medium firmness option is the shortest Serta king here.

Our 4 picks

1 Best overall

Serta Five Star Tranquility 10" King

Best for: Combination sleepers seeking zoned lumbar support

Size

King (what this guide is about)

Thickness

10 inches

Firmness

Medium-Firm

Support Core

Durable coils

Comfort Layer

PillowSoft Aire and PillowSoft Foams

Cover Material

Airflow-enhancing cover

View on Amazon: Serta Five Star Tranquility 10" King Affiliate link

The Serta Tranquility is a 10-inch medium firmness king mattress combining coils with foam layers. It features a durable coil support core and zoned lumbar foam targeting lower back pressure. The breathable cover and airflow-enhancing design aim to keep you cool. This bed-in-a-box model is ideal for combination sleepers who need balanced support and alignment without excessive sinkage.

Pros

• 10-inch profile with durable coil support core
• Zoned lumbar foam targets lower back and hips
• Breathable airflow-enhancing cover promotes cooler sleep
• CertiPUR-US certified foams for safety

Cons

• 10-inch thickness is thinner than the 12-inch and 13.5-inch competitors
• No smart features or app connectivity listed
• 90.3-pound weight makes handling difficult for one person

Good fit if

• You are a combination sleeper needing balanced support
• You prefer a medium firmness feel for alignment
• You want zoned lumbar support for lower back relief

Skip if

• You need a plush, deep-contouring feel
• You require a thicker 12-inch or taller profile
• You want smart connectivity or app control

Verdict: The Serta Tranquility 10" Medium King offers solid zoned support and breathability for combination sleepers who prefer a medium feel, though its 10-inch height is lower than other Serta king options on this list.

2 Best budget

Serta Sleeptrue Firm 12" King

Best for: Back sleepers needing firm lower back support

Size

King (what this guide is about)

Thickness

12 in

Firmness

Firm

Mattress Construction

Memory Foam

Support Core

Serta Foam Core

Comfort Layer

Cool Twist Gel Memory Foam

View on Amazon: Serta Sleeptrue Firm 12" King Affiliate link

This Serta Sleeptrue mattress uses cooling gel memory foam for a firm, 12-inch profile. It features three support zones designed for lower back care and a durable foam core for edge-to-edge support. The breathable cover promotes airflow. It arrives compressed in a box, requiring up to 72 hours to expand. You get a stable, supportive surface for back pain relief.

Pros

• Cooling gel memory foam for heat dissipation
• Three support zones for lower back care
• Durable foam core for consistent edge support
• Breathable cover promotes airflow

Cons

• Firm feel may not suit side sleepers
• Takes up to 72 hours to fully expand
• One to two weeks to air out

Good fit if

• You need firm support for lower back pain
• You prefer a 12-inch thick memory foam bed
• You want cooling gel technology in your mattress

Skip if

• You prefer a soft or medium plush feel
• You need immediate use without expansion time
• You want a hybrid or innerspring construction

Verdict: Serta Sleeptrue Firm 12" King offers targeted lower back support through its firm gel memory foam and three-zone design. It fits you if you prioritize spinal alignment and cooling in a durable, high-profile foam bed.

3 Best premium

Serta Perfect Sleeper Ultimate 13.25" Plush King

Best for: Side sleepers needing plush comfort and edge support

Size

King (what this guide is about)

Thickness

13.25"

Firmness

Plush

Support Core

High-density coil system

Comfort Layer

Cool Twist Gel Memory Foam

Certification

CertiPUR-US

View on Amazon: Serta Perfect Sleeper Ultimate 13.25" Plush King Affiliate link

This Serta mattress offers a plush feel with a 13.25-inch profile. It combines cooling gel memory foam with a zoned coil system for targeted support. The BestEdge foam rail reinforces the edges to prevent roll-off. It fits on most bed frames, including adjustable bases. You get a cool, contouring sleep surface designed for comfort and airflow.

Pros

• 13.25-inch plush profile for cushioning
• Cool Twist Gel memory foam for heat dissipation
• Zoned coil design supports lower back and hips
• BestEdge foam rail reduces edge roll-off

Cons

• Heavier at 97.4 pounds
• No adjustable firmness settings
• Plush feel may not suit back sleepers

Good fit if

• You prefer a plush, contouring sleep surface
• You need strong edge support for sitting
• You want zoned support for your hips

Skip if

• You prefer a firm, supportive feel
• You need a lightweight mattress for moving
• You want adjustable firmness levels

Verdict: Serta Perfect Sleeper Ultimate 13.25" Plush King is a heavy, plush mattress ideal for side sleepers who value edge support and cooling comfort. It suits those who want a traditional, contouring feel without electronic adjustments.

4 Also great

Serta 10" Cooling Gel Memory Foam King

Best for: Sleepers seeking cooling gel and medium support

Size

King (what this guide is about)

Thickness

10 in

Firmness

Medium

Mattress Construction

Gel memory foam

Support Core

Serta foam core

Comfort Layer

Gel memory foam

View on Amazon: Serta 10" Cooling Gel Memory Foam King Affiliate link

This Serta King mattress uses a 10-inch profile with a medium feel. It features gel memory foam in the comfort layer to contour your body while promoting airflow. The Serta foam core provides durable support from edge to edge. Weighing 91 pounds, it arrives compressed in a box for easy setup. This model suits sleepers who prefer a balanced, cooling surface.

Pros

• Gel memory foam comfort layer for cooling
• Medium firmness level for balanced support
• Edge-to-edge support from the foam core
• 100-night sleep trial included

Cons

• 10-inch thickness is thinner than competitors
• 91-pound weight makes moving difficult
• No remote or app control features

Good fit if

• You want a medium feel with cooling gel
• You need a mattress that fits through narrow hallways
• You prefer edge-to-edge support

Skip if

• You need a taller 12-inch or 13.5-inch profile
• You prefer a firm or extra-firm feel
• You want a heavier, more substantial build

Verdict: Serta 10" Cooling Gel Memory Foam King offers a cooling medium feel with edge support, fitting side or back sleepers who prioritize airflow over height.

Specifications side by side

How to choose the right one

1. Check the firmness level

   Match the firmness rating to your primary sleeping position. The Serta Sleeptrue Firm 12" King uses a firm feel to target lower back support for back sleepers. This design helps maintain spinal alignment during the night. Side sleepers often need a softer surface to relieve pressure on hips and shoulders. Combination sleepers might prefer the medium feel of the Five Star Tranquility 10" King. This balance allows for easier movement without sinking too deeply. Choose the rating that supports your body’s natural curve.

2. Consider the mattress height

   Thickness affects how easy it is to get in and out of bed. The Serta Perfect Sleeper Ultimate 13.25" Plush King offers a high profile at 13.3 inches. This height provides a traditional, elevated feel that some buyers prefer. The Serta Five Star Tranquility 10" King sits lower at 10 inches. This slimmer profile may suit those who find taller beds difficult to climb. Consider your mobility and personal preference for bed height when making your decision.

3. Evaluate the cover material

   The cover material influences temperature regulation and comfort. The Serta 10" Cooling Gel Memory Foam King features a cooling gel cover. This material helps draw heat away from your body for a cooler sleep surface. This feature is ideal for hot sleepers who prioritize airflow. Other models in this list do not specify a cooling gel cover. If temperature control is a priority, check the cover material details carefully. This spec can significantly impact your comfort throughout the night.

4. Review the special features

   Look for convenience features that simplify your purchase and setup. Several models in this guide include the Bed in a Box feature. This means the mattress is compressed and shipped in a manageable package. You can easily move it into your bedroom and unbox it yourself. This feature reduces delivery complexity and handling hassles. Check the attributes list to confirm if this feature is included. It is a practical benefit for those who want a straightforward setup process.

5. Assess the weight capacity

   The weight of the mattress indicates its density and durability. The Serta Perfect Sleeper Ultimate 13.25" Plush King weighs 97.4 pounds. This heft suggests a dense, plush construction that may offer robust edge support. The Serta Five Star Tranquility 10" King weighs 90.3 pounds. Heavier mattresses often provide a more stable feel and may last longer. Compare the weight specifications to gauge the build quality. This data point helps you understand the physical presence of the bed.

Frequently asked questions

See also

• best serta medium mattresses
• best serta full mattresses
• best serta king mattresses
• best king mattress toppers