Three Quarter Mattress: Size, Uses & Where to Find One

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.

02Three Quarter Mattress Dimensions

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.

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.

03Who This Mattress Is For

Antique or Custom Bed Frames

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.

Small Rooms and Tight Spaces

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.

Guest Rooms

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.

Daybeds and Multi-Use 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.

Not the Right Choice If:

• You're buying for two adults who will share the bed regularly — a full or queen gives both partners more room
• Standard bedding is important to you — three quarter sheets are harder to find and more expensive than twin or full
• You don't already have a frame that requires this size

04What to Look for in a Three Quarter Mattress

Verify Your Frame Dimensions First

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.

Thickness and Clearance

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.

Material and Support

For a single adult, most common mattress constructions work well in this size:

• Memory foam: Good pressure relief and motion absorption. Works well for guest rooms where you want quiet, comfortable sleep for one person.
• Innerspring: Traditional feel, good airflow, easy to find in custom sizes. Works well for daybeds that need to look and feel like seating during the day.
• High-density foam: Solid support with less bulk. A good choice when you need support with a thinner profile for a low-clearance frame.
• Natural latex: Durable and breathable. Worth considering if the mattress will see regular use for years — latex holds its shape much longer than basic foam.

Custom Sizing

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.

05How to Get a Three Quarter Mattress

Three quarter mattresses are not standard retail inventory — most big-box stores don't carry them. Your best options:

• Specialty mattress retailers: LA Mattress Store can help you find or custom-order this size. Come into any of our five LA showrooms or contact us by phone or chat with your exact measurements.
• Online custom mattress services: Several online retailers specialize in non-standard sizes. Be sure to read reviews and understand the return/exchange policy before ordering something you can't try first.
• Mattress toppers as a workaround: In some cases, a twin mattress with a wide mattress topper can approximate the feel of a three quarter without requiring a fully custom piece. This is worth discussing if budget is a constraint.

06Get a Quote

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 →

07Frequently Asked Questions

What are the dimensions of a three quarter mattress?

Standard dimensions are 48 inches wide by 75 inches long. Some manufacturers vary slightly — always measure your frame before ordering.

Is a three quarter mattress the same as a double?

No. A double (full) mattress is 54 inches wide. A three quarter is 48 inches wide — 6 inches narrower. They are not interchangeable.

Can two adults sleep on a three quarter mattress?

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.

Are three quarter mattresses still made?

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.

Where can I find sheets and bedding for a three quarter mattress?

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.

How thick should a three quarter mattress be?

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.

What's the difference between a three quarter and a twin XL?

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.

Can I get a three quarter mattress in a specific material or firmness?

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.