King Size Futon Mattresses

King size futon mattresses give two sleepers a full king sleeping surface on a platform bed, a tatami platform or the floor. Built from natural cotton, wool and latex, they offer the firm, breathable support futon mattresses are known for, in a size large enough to serve as a primary bed. At this width they are used flat rather than folded on a convertible frame.

Set a king futon mattress on a king size platform bed or a Japanese tatami bed, or build a floor bed with tatami mats. A Guide to the Japanese Sleep System covers how the layers work together.

Natural fibers need airflow, so read The Floor Sleeper's Guide to Airflow before setting up a floor bed, and add a mattress protector or futon cover. For a smaller bed, see queen size futon mattresses.

Happy couple on a futon mattress

Beyond the Dorm Room: Natural Materials

Many people associate "futons" with cheap, lumpy polyurethane foam. We do things differently. Our cotton futon mattresses are handcrafted using layers of dense, unbleached cotton batting and natural wool. This creates a breathable, supportive core that resists sagging and keeps you cool. For those seeking extra resilience, our hybrid models incorporate natural latex or CertiPUR-US® foam to add a "spring-like" feel without the metal coils, ensuring a comfortable sleep surface that lasts for years, not semesters.

Girl sleeping on a tufted floor mattress

Sofa or Bed? Choosing the Right Profile

One of the biggest benefits of a futon is versatility. If you plan to use your mattress primarily on a bi-fold sofa frame, we recommend our 6-8 inch profiles, which offer enough cushion for sitting but are flexible enough to fold at the crease. If you are building a permanent sleeping setup on a platform bed, you can opt for our thicker, denser Japanese-style mattresses for maximum spinal support. No matter the frame, our tufted design keeps the filling from shifting, ensuring consistent comfort in any position.

Natural mattress components

Futon Basics

Explore Our Mattress Collections

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  • Futon Mattress Sketch

    Futon Mattresses

    Versatile and foldable. Durable natural blends designed to flex easily for sofa frames or lay flat for guests.

    Shop Futon Mattresses 
  • Japanese Futon Mattress Sketch

    Japanese-Style Handmade Futons

    Masterfully hand-tufted. Dense, firm layers of cotton and wool for traditional support that resists settling.

    Shop Handmade 
  • Shiki Futon Mattress Sketch

    Shikibutons

    Authentic floor sleeping. Lightweight, thin and rollable cotton mattresses for a grounded, minimalist lifestyle.

    Shop Shikibutons 
  • Baby Mattress Sketch

    Baby Mattresses

    Pure safety. Firm, breathable organic materials free from toxins to support your baby's healthy development.

    Shop Baby Mattresses 
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Frequently Asked Questions: Futon Mattresses

Can I sleep on a futon every night?

Absolutely. Our futon mattresses are engineered for nightly use. Because they are constructed with dense layers of cotton (and optional foam and latex), they provide firm, ergonomic support similar to a high-end firm mattress. They are ideal for back sleepers and anyone seeking a grounded, supportive sleep surface.

Will these fit my existing futon frame?

Yes. Our mattresses adhere to standard US bedding dimensions.

  • Full Size Futon: 54" x 75" (The most common size for sofa convertibles).
  • Queen Size Futon: 60" x 80" (Common for guest rooms and larger sofas).

We also offer the entire range, including Twin, Twin XL, King, and California King. We can even craft custom sizes for antique beds, RVs, or unique projects—just contact us for a quote.

What is the difference between a Futon and a Shikibuton?

It mostly comes down to thickness and usage. A Shikibuton is a traditional, thin (3-4") Japanese mat designed to be rolled up and stored daily. A Western-style Futon is typically thicker (6-8") and heavier. It is designed to stay on a frame (sofa or bed) permanently and provides more cushion for side sleeping.

How do I clean a natural futon?

Because natural fibers are absorbent, we highly recommend using a removable futon cover or mattress protector. If a spill occurs, spot clean with mild soap and water—do not soak the mattress. Regular sunning (placing the mattress in direct sunlight) helps refresh the cotton, kill bacteria, and evaporate moisture.

Are these mattresses fire safe?

Yes. We prioritize safety without chemicals. Most of our mattresses use a layer of natural wool as a fire barrier to meet federal safety standards (16 CFR 1633). For vegan options, we use cotton treated with natural boron. We do not use fiberglass or chemical flame retardant sprays.

Why is the mattress so heavy?

Quality materials have weight. A 100% foam mattress is light because it is mostly air. Our mattresses are filled with layers of dense, compressed cotton and wool. A Queen futon mattress can weigh between 50-90 lbs depending on the core. This density is what provides the durability and support that prevents the mattress from bottoming out.

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