A split king adjustable bed combines the width of a traditional king-size sleeping surface with two independently moving sides. The arrangement is particularly useful for couples who prefer different sleeping positions, firmness levels, or head and foot elevations. Costco carries several mattress-and-adjustable-base combinations that use the split king format.
A split king generally consists of two Twin XL mattresses positioned side by side. Each mattress measures approximately 38 inches wide by 80 inches long, creating a combined sleeping surface roughly equivalent to a standard king.
The major difference is that each side can move independently when paired with compatible adjustable bases.
One sleeper can raise the head while the other keeps the bed flat. One side can also be raised at the feet without changing the position of the opposite side.
This arrangement can be useful for couples with different sleeping preferences.
A complete bundle generally combines four main components:
The exact package depends on the manufacturer.
For example, Costco's Tempur-Pedic Supreme mattress-and-base set specifies that the Split King configuration includes two Twin XL mattresses and two Twin XL adjustable power bases.
Some packages may also include features such as massage motors, USB charging ports, under-bed lighting, or specialized mattress materials.
The primary function of an adjustable base is powered positioning.
The head section can be elevated for activities such as reading or watching television. The foot section can also be raised, creating a more customized sleeping position.
Some bases provide numerous positioning combinations rather than only a few fixed settings.
The Sleep Science Q-Series, for example, includes nearly unlimited head and foot lift positions and a zero-gravity preset.
Zero gravity is a popular feature on adjustable beds.
The position raises the upper body and legs in a way intended to distribute body weight more evenly across the mattress.
Adjustable-bed manufacturers often promote this position for relaxation and pressure management. However, individual comfort can differ significantly.
The position is also useful for activities such as reading, watching television, or using a laptop while reclining.
Independent movement is one of the biggest differences between a split king and a conventional king adjustable bed.
With a standard king base, both sides generally move together.
With a split king setup, each half has its own motor system. One person can raise the head while the other remains relatively flat.
This can be particularly useful when sleeping preferences differ.
For example, one person might prefer an elevated head position while the other prefers a flatter sleeping position.
Not every mattress is designed for an adjustable base.
Flexible mattress constructions generally work better with powered movement because the mattress needs to bend as the base changes position.
Memory foam, latex, and many hybrid mattresses are commonly designed for adjustable bases.
Costco's own information on king mattresses for adjustable beds notes that compatibility should be confirmed before pairing a mattress with an adjustable base.
A conventional innerspring mattress may not provide the necessary flexibility unless the manufacturer specifically states that it can be used with an adjustable foundation.
Memory foam is frequently paired with adjustable bases.
The material can flex as the platform moves while maintaining contact with the body.
A memory foam mattress may also provide strong motion isolation, which can be useful when two sleepers share a split king.
Costco currently lists Sleep Science memory foam combinations such as the 13-inch Align IQ Euro Top set with an adjustable base.
Hybrid mattresses combine foam comfort layers with individually pocketed coils or other support structures.
They can provide a balance between contouring and support while still offering sufficient flexibility for compatible adjustable bases.
Costco currently lists a Sleep Science Solara 14-inch hybrid mattress with an adjustable base, including a Split King configuration.
Hybrid construction may also provide more airflow than some dense all-foam designs.
Tempur-Pedic is among the premium mattress brands sold through Costco.
The Tempur-Pedic Supreme 11.5-inch Medium Hybrid mattress with Ergo Adjustable Base is sold in a Split King configuration consisting of two Twin XL mattresses and two Twin XL adjustable power bases. The base includes infinite ergonomic positions, USB ports, and a wireless remote.
Costco's current listing shows a starting price of $2,399.99 for the set, with pricing subject to change.
Another Tempur-Pedic Supreme configuration is listed with medium or firm mattress choices and an Ergo adjustable base.
Sleep Science offers several adjustable-bed combinations through Costco.
The Align IQ Euro Top mattress with adjustable base uses memory foam construction and is listed in Split King format. The product page currently shows a starting price of $1,799.99.
The Solara 14-inch hybrid model is another example. It combines memory foam with pocketed coils and includes adjustable-base configurations.
The exact specifications differ between models, so mattress thickness, firmness, base features, delivery method, and included services should be reviewed separately.
Some adjustable bases include built-in massage motors.
Massage settings can produce vibration through different sections of the bed. Depending on the base, several intensity levels or programmed modes may be included.
For example, Costco's GhostBed Luxe mattress with adjustable base lists 15 whisper-quiet massage modes.
Massage functionality is primarily a comfort feature and should not be considered a medical treatment.
USB ports are another common feature on premium adjustable bases.
These ports can allow phones, tablets, or other compatible devices to be charged from the bedside without requiring a separate wall charger.
The Tempur-Pedic Ergo base listed by Costco includes USB ports along with wireless controls.
Some adjustable bases incorporate LED lighting underneath the bed.
This can provide low-level illumination for nighttime movement without requiring a bright bedroom light.
GhostBed's adjustable base, for example, lists under-bed LED lighting among its features.
The feature can be particularly useful in bedrooms where floor-level lighting is limited.
Wireless remotes are commonly included with powered adjustable bases.
Depending on the model, the remote may control:
Some systems also include programmable memory buttons.
The Sleep Science Q-Series, for example, includes a backlit wireless remote with three programmable memory buttons.
A split king can reduce some forms of partner disturbance because each sleeper has an independent mattress and base.
Movement on one side does not necessarily cause the same degree of movement across the entire sleeping surface as a single mattress on a shared adjustable platform.
However, the center seam remains noticeable to some sleepers.
A mattress bridge or specialized bedding accessory can sometimes make the center transition less noticeable, although compatibility should be checked before adding accessories.
Standard king sheets are not always ideal for a split king adjustable configuration.
Many households use two Twin XL fitted sheets and a king-size top sheet.
Another approach is a dedicated split-king sheet set.
Fitted sheets need sufficient elasticity and depth to remain secure while the head and foot sections move.
Mattress protectors should also be designed for adjustable bases and flexible mattresses.
Some adjustable bases can be placed inside compatible bed frames, while others are intended to stand independently.
The Sleep Science Q-Series, for example, is described as a zero-clearance base that can fit into an existing bed frame or platform bed, with or without legs.
Compatibility depends on the exact frame dimensions and base design.
A traditional headboard may require brackets or a separate mounting system.
Delivery terms vary by product.
Some Costco adjustable-bed sets include delivery, setup, and haul-away services. The current Tempur-Pedic Supreme listing, for example, states that delivery, setup, and haul-away are included.
Other products may be delivered directly to the home without room-of-choice setup.
The Sleep Science Solara listing currently specifies delivery only, with setup and haul-away handled separately.
These differences can have a meaningful effect on the overall purchasing experience.
Split king adjustable bundles can span a broad price range.
The current Costco listings reviewed show examples starting around $1,599.99 for the Sleep Science Solara 14-inch hybrid combination, $1,799.99 for the Sleep Science Align IQ combination, and $2,399.99 for the Tempur-Pedic Supreme 11.5-inch Medium Hybrid with Ergo Adjustable Base.
Prices can change because of promotions, membership pricing, product updates, and inventory.
A lower-priced bundle may also include fewer features or different delivery terms, so the headline price alone does not provide a complete comparison.
Several factors influence the total price of a split king adjustable bed:
Memory foam, hybrid, latex, and premium specialty materials can have different price points.
Thicker mattresses may use additional materials and construction layers.
Massage, USB ports, lighting, programmable positions, and advanced controls can increase the price.
Premium mattress brands generally occupy a higher price segment.
Room delivery, installation, setup, and old-mattress removal can affect the total cost.
Retail pricing can change during seasonal promotions or limited-time sales.
Several specifications deserve attention before selecting a split king adjustable bundle.
Confirm that the mattress is designed for use with an adjustable base.
Check the manufacturer's weight limits for each side of the base.
Make sure the mattress thickness is compatible with the base and fitted sheets.
Compare the number of presets and programmable positions.
Check whether massage is included and how many settings are provided.
USB ports and wireless controls may be useful for bedside convenience.
Determine whether the package includes room delivery, setup, and old-mattress removal.
Review separate warranties for the mattress and adjustable base because the coverage terms may differ.
A split king setup can provide several practical benefits.
Each sleeper can select a different head or foot position.
The combined width matches a conventional king-size bed.
Compatible memory foam and hybrid mattresses can be paired with adjustable bases.
Wireless controls, preset positions, USB charging, and lighting can add functionality.
Separate mattresses can limit some movement between sleepers.
There are also factors that may make a split king less suitable for some bedrooms.
A split system requires two mattresses and two powered bases.
The division between the mattresses can be noticeable.
Two mattresses, two bases, and multiple controls create more components than a conventional king setup.
Specialized sheets or two Twin XL fitted sheets may be necessary.
Adjustable bases can be heavy and difficult to move.
The Sleep Science Q-Series Split King base, for example, weighs 160 pounds according to Costco's specifications.
Neither configuration is universally better.
A regular king mattress provides one continuous sleeping surface and can be simpler for couples who prefer the same sleeping position.
A split king provides greater individual control.
For couples with different preferences, the independent movement can be a major advantage. For sleepers who frequently move across the entire width of the bed or dislike a center seam, a conventional king may feel more natural.