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Sleeper Sofa Mattress Sizes

Three of the size names in this category describe something smaller than the name implies. Here is the full reference, so you order the right one once.

Folded bed linens and pillows stacked on a made bed

This is a reference page, and it exists because three size names in this category describe something smaller than you would reasonably assume. People order a queen and receive something eight inches shorter; people order a twin-width mattress for a tri-fold and receive something seven inches narrower.

The three traps, up front. A sofa-bed queen is 58 by 72 inches, not 60 by 80. A cot-size tri-fold is 31 inches wide, not 38. And a cabinet bed sold as queen can contain a 53-by-75-inch mattress, which is nearer a full.

The full size reference

Every size in this category, measured

Bedroom twin
38 × 75 in.
Bedroom twin XL
38 × 80 in.
Bedroom full
54 × 75 in.
Bedroom queen
60 × 80 in.
Full futon mattress
75 × 54 in. — same plan as a bedroom full
Sofa-bed queen
58 × 72 in. — 8 in. shorter than a bedroom queen
Cot-size tri-fold
75 × 31 in. — 7 in. narrower than a twin
Cabinet bed tri-fold (Creden-ZzZ)
53 × 75 in. despite the queen label
Cabinet bed tri-fold (Night & Day Cube)
80 × 63 × 6 in.
Floor futon twin / full / queen
39 × 80 / 54 × 80 / 60 × 80 in.

Two useful patterns. Futon mattresses and floor futons use real mattress plans, so ordinary sheets fit. Sofa-bed and cabinet-bed mattresses do not, because they are dimensioned to a cavity rather than to a bedding standard.

Convertible sofas do not have a size at all

A split-back convertible has no mattress, so it has no mattress size — it has an opened dimension, and every model’s is different.

Opened dimensions, which are not sizes

Serta Rane / Chelsea
66.1 × 37.6 in.
Novogratz Brittany
70.5 × 43.5 in.
DHP Emily
71 × 43.5 in.
Novogratz Tallulah
73 × 44 in.
Novogratz Vintage Tufted II
81.5 × 44 in.
Novogratz Brittany Sectional
88 × 66 in.

No fitted sheet is made for any of these, and there is no trick that makes one work. What people use in practice is a flat sheet tucked, or a duvet folded in half and used as both layers. A fitted full sheet on a 43.5-inch-wide surface pulls at the corners and comes off in the night.

Depth limits by frame, which matter as much as plan size

How thick you can go

Fold-out sofa bed
About 4.5 in. — the mattress folds into a cavity
Bi-fold futon frame
Up to 8 in. — folds once, in the open
Tri-fold / cabinet bed
About 6 in. — folds twice
Trundle drawer
6 in. or less, or the tray will not close
Daybed
The frame's side rail height — Novogratz Bushwick publishes 8 in.
Wall bed
8–12 in. conventional; Bestar states 60–90 lb as well

A wall bed is the only format here with a mattress weight limit as well as a depth limit, because the mechanism is counterbalanced. Bestar specifies 60 to 90 pounds; Lori specifies 80 pounds maximum for a queen.

What bedding actually fits what

Full futon mattress (75 × 54 in.). Standard full sheets fit. Use a shallow-pocket or low-profile fitted sheet on an eight-inch mattress — most fitted sheets are now cut for 10 to 14 inches and will billow.

Sofa-bed queen (58 × 72 in.). Queen sheets, loose but usable. No mattress protector exists in this size in general retail; a flat waterproof pad under the sheet is the practical answer.

Cot-size tri-fold (75 × 31 in.). Cot sheets exist and are hard to find. Most people use a flat sheet.

Daybed (38 × 75 in.). Ordinary twin sheets, which after everything above is a relief.

Wall bed (60 × 80 in.). Ordinary queen everything, and the bedding stays on the bed under straps, which is one of the format’s best features.

How to measure the frame you already have

Open the sofa fully. Measure the existing mattress flat: width across, length along, and depth at the edge rather than the middle, because the middle has compressed.

Then close the sofa and measure the cavity the mattress lives in. That second number is your real depth ceiling, and it is usually about half an inch less than the mattress currently in there, because the old one has thinned.

Order to the smaller number. A replacement half an inch too thick stops the sofa closing, and there is no adjustment. Replacements are covered in the best sleeper sofa mattresses.

Some links on this page are affiliate links. If you buy through one we may earn a commission at no extra cost to you, and it does not change what we recommend or how we rank it. Full disclosure.

At a glance

Replacements in the sizes that exist

Tap any row to jump to the full write-up. Scores are our own, from the rubric on how we choose — not customer ratings.

#ProductBest forScorePrice
01
Close view of an upholstered sofa cushion and seamIllustrative

Classic Brands 4.5-Inch Cool Gel Sleeper Sofa Replacement Mattress

The fix for a pull-out you can feel the bar through: 4.5 inches of gel memory foam, 44 lb, and a 25-year warranty.

Replacing a pull-out mattress7.7
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02
A plain mattress on a simple white bed frameIllustrative

DHP 8 Inch Independently Encased Coil Futon Mattress

Eight inches with 15-gauge pocket coils — the closest a drop-in futon mattress gets to a real bed, and it fits any standard full futon frame.

Everyday sleeping on a futon frame8.1
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03
A folded block of foam mattress standing on a hard floorIllustrative

Milliard 6-Inch Tri-Fold Memory Foam Mattress

The one that goes in a closet: 75 by 31 inches flat, 31 by 25 by 18 inches folded, with 1.5 inches of memory foam over a 4.5-inch base.

Storing a guest bed in a closet7.8
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04
A small guest bedroom with a neatly made bed against a pale wallIllustrative

Zinus 8 Inch Green Tea Memory Foam Mattress

Two inches of memory foam, two of comfort foam, four of base — the standard answer for a daybed or trundle that needs a real mattress under 10 inches.

Daybeds and trundles8.0
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How we picked

One representative mattress per size class — fold-out sofa bed, full futon, cot-size tri-fold and conventional — so the reference table maps onto something orderable. Chosen for published dimensions rather than comfort, because this page exists to stop the wrong size arriving.

Replacing a pull-out mattress

Classic Brands 4.5-Inch Cool Gel Sleeper Sofa Replacement Mattress

Classic Brands

Close view of an upholstered sofa cushion and seamIllustrative — category photo, not this unit

The fix for a pull-out you can feel the bar through: 4.5 inches of gel memory foam, 44 lb, and a 25-year warranty.

What it's bad at

A "queen" sofa bed mattress is 58 by 72 inches, not 60 by 80. Your queen sheets will not fit it, and nor will a standard queen mattress protector.

Our score — 7.7 / 10

Comfort7
Depth5
Foldability9
Weight7
Value8
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Specifications

Folded footprint
Ships compressed
Open footprint
58 in. W x 72 in. L x 4.5 in. H (sofa-bed queen)
Clearance in front
Not applicable — mattress.
Doorway minimum
Ships compressed, so any doorway
Sleep surface
58 x 72 in. — sofa-bed queen, smaller than a bedroom queen
Mattress
4.5 in. gel-infused memory foam, CertiPUR-US certified
Fold mechanism
Folds into most fold-out sofa frames
Weight capacity
NOT STATED BY MANUFACTURER
Assembly
None. 44 lb. 25-year warranty.
Renter-safe?
Yes
Price
Check price on Amazon

Source: Amazon.com product listing, recorded 27 Sep 2026. Any field the listing does not state is marked as such rather than estimated.

Everyday sleeping on a futon frame

DHP 8 Inch Independently Encased Coil Futon Mattress

DHP

A plain mattress on a simple white bed frameIllustrative — category photo, not this unit

Eight inches with 15-gauge pocket coils — the closest a drop-in futon mattress gets to a real bed, and it fits any standard full futon frame.

What it's bad at

59 lb of mattress on a frame that has to fold. It is stiff to bi-fold the first dozen times, and a light frame will feel the weight.

Our score — 8.1 / 10

Comfort8
Depth9
Foldability6
Weight5
Value8
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Specifications

Folded footprint
Ships rolled: 59 in. L x 13 in. W x 13 in. H carton
Open footprint
75 in. L x 54 in. W x 8 in. H (full)
Clearance in front
Not applicable — this is a mattress, not a frame.
Doorway minimum
Passes any standard doorway in the shipping carton (13 in. square section)
Sleep surface
75 x 54 in. — standard full
Mattress
8 in.; 15-gauge independently encased pocket coils with foam and polyester layers
Fold mechanism
Bi-folds with the frame
Weight capacity
NOT STATED BY MANUFACTURER
Assembly
None. 59 lb net, 71 lb shipped.
Renter-safe?
Yes
Price
Check price on Amazon

Source: Brand listing via Walmart.com and Amazon.com product pages, recorded 27 Sep 2026. Any field the listing does not state is marked as such rather than estimated.

Storing a guest bed in a closet

Milliard 6-Inch Tri-Fold Memory Foam Mattress

Milliard

A folded block of foam mattress standing on a hard floorIllustrative — category photo, not this unit

The one that goes in a closet: 75 by 31 inches flat, 31 by 25 by 18 inches folded, with 1.5 inches of memory foam over a 4.5-inch base.

What it's bad at

Cot width. At 31 inches it is narrower than a twin, and the two fold lines are findable through the foam if you sleep on your side.

Our score — 7.8 / 10

Comfort6
Depth6
Foldability10
Weight9
Value8
Check price on Amazon →

#ad how we earn · we do not print prices

Specifications

Folded footprint
31 in. x 25 in. x 18 in. folded
Open footprint
75 in. L x 31 in. W x 6 in. H flat
Clearance in front
Not applicable — floor mattress.
Doorway minimum
Folded section is 31 in. wide, so any standard doorway
Sleep surface
75 x 31 in. — cot size, narrower than a twin
Mattress
6 in.; 1.5 in. of 3 lb memory foam over a 4.5 in. support base
Fold mechanism
Tri-fold
Weight capacity
NOT STATED BY MANUFACTURER
Assembly
None. Removable washable cover with a non-slip bottom.
Renter-safe?
Yes
Price
Check price on Amazon

Source: Manufacturer listing, milliardbrands.com, plus the Amazon.com product page, recorded 27 Sep 2026. Any field the listing does not state is marked as such rather than estimated.

Daybeds and trundles

Zinus 8 Inch Green Tea Memory Foam Mattress

Zinus

A small guest bedroom with a neatly made bed against a pale wallIllustrative — category photo, not this unit

Two inches of memory foam, two of comfort foam, four of base — the standard answer for a daybed or trundle that needs a real mattress under 10 inches.

What it's bad at

The twin is rated to 250 lb where every other size is 500 lb, which matters because twin is exactly the size daybeds take.

Our score — 8.0 / 10

Comfort8
Depth7
Foldability1
Weight6
Value9
Check price on Amazon →

#ad how we earn · we do not print prices

Specifications

Folded footprint
Ships compressed and rolled in a box
Open footprint
Standard mattress sizes, 8 in. deep
Clearance in front
Not applicable — mattress.
Doorway minimum
Ships rolled, so any doorway
Sleep surface
Standard Twin through King
Mattress
8 in.; 2 in. memory foam + 2 in. airflow comfort foam + 4 in. high-density base
Fold mechanism
None — does not fold
Weight capacity
250 lb in Twin; 500 lb in all other sizes
Assembly
None. Expands in a few hours, settles within 48.
Renter-safe?
Yes
Price
Check price on Amazon

Source: Manufacturer listing, zinus.com, plus the Amazon.com product page, recorded 27 Sep 2026. Any field the listing does not state is marked as such rather than estimated.

Answers

Common questions

What size is a queen sleeper sofa mattress?
58 by 72 inches — for example the Classic Brands 4.5-inch replacement, at 58 by 72 by 4.5 inches. A bedroom queen is 60 by 80. They are not interchangeable, and ordering a bedroom queen means the sofa will not close.
What size sheets fit a sleeper sofa?
For a fold-out sofa-bed queen at 58 by 72 inches, queen sheets are loose but usable. For a convertible split-back, nothing fits — those open to non-standard sizes like 70.5 by 43.5 inches, and the practical answer is a flat sheet or a folded duvet. A full futon mattress at 75 by 54 inches takes standard full sheets.
What size is a full futon mattress?
75 by 54 inches, the same plan as a standard full mattress, with depth ranging from six to eight inches. That is why standard full sheets fit, and why a twin mattress will not fit a full futon frame.
How thick can a sleeper sofa mattress be?
About 4.5 inches for most fold-out frames, because the mattress has to fold into a cavity. A bi-fold futon frame takes eight inches, a tri-fold about six, and a trundle drawer six or less. Measure the cavity in your own sofa rather than the mattress currently in it, which has compressed.
Is a cabinet bed really a queen?
Check the measured mattress. The Arason Creden-ZzZ is sold as a queen cabinet bed and its included tri-fold is 53 by 75 inches, which is essentially a full. The Night & Day Cube's optional mattress is 80 by 63 by 6 inches, much closer to a genuine queen.

Sources

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