The three quarter mattress is a genuinely useful size that most people haven't heard of — until they need one. It fills the gap between twin and full, making it the right answer for a specific set of situations where standard sizes just don't fit.
If you have an antique bed frame, a small guest room, an RV, a daybed, or a custom-built space that doesn't match standard dimensions, this guide is for you.
A standard three quarter mattress measures 48 inches wide by 75 inches long. Some variations exist — manufacturers occasionally produce them at 48" × 72" or 48" × 80" — so always verify the exact dimensions before ordering.
| Size | Width | Length | Notes |
|---|---|---|---|
| Twin | 38" | 75" | Standard single-person size |
| Three Quarter | 48" | 75" | Wider than twin, shorter than full |
| Full / Double | 54" | 75" | Standard "double" size |
| Queen | 60" | 80" | Most popular couples size |
The three quarter is 10 inches wider than a twin — enough to make a meaningful difference for an adult — but 6 inches narrower than a full and 5 inches shorter than a standard queen-length mattress.
Three quarter beds were common in the late 19th and early 20th century. If you've inherited or purchased a period antique bed frame, there's a good chance it's designed for this size. A twin is too narrow; a full won't fit. The three quarter is often the only correct answer.
At 48 inches wide, a three quarter mattress fits in spaces where a full mattress simply can't. If a full mattress would leave no room to walk around the bed, or block closet doors, a three quarter solves the problem while still giving one adult comfortable sleeping room.
For a guest room that sees occasional use by single adults, a three quarter provides more comfort than a twin without taking up full-width floor space. It reads as more comfortable and inviting than a twin while still leaving room in tighter spaces.
Some daybed frames are sized for three quarter mattresses. The dimensions also work well in studio apartments or multi-use rooms where the bed functions as a sofa during the day.
Before ordering, measure your bed frame's interior sleeping surface — width and length both. Don't assume it's 48" × 75". Older frames especially can vary by a few inches, and a mattress that's even 2 inches too wide or too long creates real problems. Measure twice, order once.
Antique bed frames often have low rail heights designed for thinner mattresses. A modern 12" profile mattress may sit significantly higher than the original design intended, which can look awkward and make it harder to get in and out of bed. Aim for a mattress profile of 8–10 inches if working with a period frame.
For a single adult, most common mattress constructions work well in this size:
If your frame's dimensions don't match standard three quarter sizing, custom sizing is available. LA Mattress Store can source or order mattresses to exact specifications — including custom height, width, and length. Contact us to discuss your measurements before ordering.
Three quarter mattresses are not standard retail inventory — most big-box stores don't carry them. Your best options:
LA Mattress Store offers custom sizing for height, width, and length. If you need a three quarter mattress — or any non-standard dimension — we're set up to help. Bring your measurements to any showroom or contact us online and we'll put together a quote based on what you need.
Phone and chat available. Our team can help you figure out the right construction, thickness, and material for your specific frame and use case.
Find a showroom → | Request a custom size quote →
Standard dimensions are 48 inches wide by 75 inches long. Some manufacturers vary slightly — always measure your frame before ordering.
No. A double (full) mattress is 54 inches wide. A three quarter is 48 inches wide — 6 inches narrower. They are not interchangeable.
It's possible, but tight. At 48 inches wide, two adults have significantly less room than on a full or queen. This size is designed for one adult or occasional shared use, not regular couple sleeping.
Yes, though not as standard retail inventory. Specialty retailers and custom mattress manufacturers still produce this size. LA Mattress Store can help source or order one.
Bedding for three quarter mattresses is available from specialty linen retailers and online. Full-size sheets are sometimes a workable substitute depending on mattress thickness — check fitted sheet dimensions carefully.
For modern comfort, 8–12 inches is typical. If you're working with an antique frame that has low rails, aim for 8–10 inches. For a standard platform or modern frame, 10–12 inches works well.
A twin XL is 38 inches wide by 80 inches long — narrower but longer than a three quarter (48" × 75"). They serve different purposes: twin XL is for taller single sleepers; three quarter is for those who need more width in a shorter space.
Yes. Custom sizing doesn't limit your material options. Memory foam, innerspring, latex, and hybrid constructions are all available in custom sizes through LA Mattress Store. Contact us with your specs.
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