How to Choose a Mattress for a Murphy Bed That Stays Flat

Updated 2026-07-13 · 1 Tier Finds

The biggest mistake people make with Murphy beds is treating them like a standard bed frame. If you put a traditional 14-inch pillow-top mattress in a wall bed, you’ll either find it impossible to close the mechanism or you'll put dangerous stress on the springs. To successfully choose mattress for murphy bed flat and functional, you have to prioritize depth and flexibility over luxury plushness.

The Golden Rule: Mind the Profile Height

Before you look at materials, check your Murphy bed's maximum mattress thickness. Most wall beds are designed for mattresses between 5 and 10 inches. If you go over that limit, the bed won't lock, or the mattress will bunch up against the wall, causing it to bow or warp over time.

A "low profile" mattress is your best bet. Look for options that are specifically marketed as being for daybeds or bunk beds, as these typically hit the 6-to-8-inch sweet spot. This ensures the bed stays flat against the support slats and folds away without fighting the hardware.

Memory Foam vs. Hybrid vs. Innerspring

Not all materials play well with folding mechanisms. Here is the practical breakdown of what actually works in a wall bed:

• Memory Foam: The gold standard for Murphy beds. They are naturally thinner, lightweight, and flexible. Because they don't have a rigid perimeter, they are less likely to snag on the frame.
• Hybrids: A good middle ground. These combine a thin coil layer with foam. They offer more bounce and better airflow than pure foam, but make sure the overall height doesn't exceed your frame's limit.
• Innerspring: Generally avoid these. Traditional innerspring mattresses are often too thick and too rigid. They can create a "trampoline effect" that makes the bed feel unstable when folded.

Matching Firmness to Your Sleeper

Since Murphy beds are often used in guest rooms, you need a "crowd-pleaser" firmness. A medium-firm feel is the safest bet for a variety of body types and sleeping positions. However, if this is your primary bed, prioritize your specific needs:

Side sleepers need a bit more give to prevent shoulder and hip pain, so a memory foam mattress with a softer top layer is ideal. Back and stomach sleepers should stick to firm options to prevent the mattress from sagging, which is a common issue with thinner mattresses over time.

Budget Tiers: What to Expect

You don't need to spend a fortune to get a quality sleep in a guest room. When browsing Mattresses on Amazon, you'll generally see three price tiers:

Budget ($150–$300): These are typically basic all-foam mattresses. They are great for occasional guests but may lack long-term durability or edge support.

Mid-Range ($300–$600): This is where you find high-density foams and entry-level hybrids. These offer a better balance of support and pressure relief, making them suitable for daily use.

Premium ($600+): These usually feature advanced cooling gels, organic materials, or sophisticated coil systems. Choose these if the Murphy bed is in a primary bedroom.

Common Mistakes and How to Avoid Them

One of the most common errors is forgetting about the "box spring" mentality. Murphy beds have built-in slats; adding a box spring or a thick topper will make the bed impossible to close. If you find your mattress is too firm, add a thin 2-inch memory foam topper rather than buying a thicker mattress.

Another mistake is neglecting the mattress straps. Because the bed is vertical for most of the day, some mattresses can shift. Use the straps provided with your Murphy bed frame to keep the mattress snug against the slats. This prevents the mattress from sliding and ensures it stays flat when you lower the bed.

Maintenance for Long-Term Flatness

To keep your mattress from developing a permanent curve or dip, rotate it 180 degrees every few months. Even though the bed spends time vertical, the pressure points remain the same when you sleep on it.

If you use a memory foam option, be mindful of heat. Foam traps heat more than springs do, so a breathable mattress protector is a practical addition to keep the bed fresh and prevent moisture buildup while it's tucked away in the cabinet.

FAQ

Can I use a standard mattress in a Murphy bed?

Only if the height is within the manufacturer's specifications (usually under 10 inches). Standard mattresses are often too thick and will prevent the bed from closing securely.

Will a memory foam mattress sag in a Murphy bed?

High-density memory foam holds its shape well. To prevent sagging, ensure your bed's support slats are in good condition and rotate the mattress regularly.

Do I need a mattress protector for a wall bed?

Yes. Because the mattress is stored in a confined space, a protector prevents dust accumulation and protects against odors or moisture that can build up inside the bed cabinet.