Bunk Bed Mattress Sizes Guide

When we hear the word bunk bed, most of us imagine the standard twin mattress bunk bed. In actuality, bunk beds come in all sorts of sizes, from the typical twin all the way up to a king.

Bunk beds are great if you have a compact bedroom, you have more people in your home than bedrooms, your children share a room or have sleepovers often, or if you’re trying to maximize the number of sleepers per bedroom.

Bunk beds don’t use any special sort of mattress sizes, so you can fit any of your favorite mattresses on a bunk bed. Whether you prefer cooling gel memory foam mattress or hybrid bed, your bunk bed mattress should fit snugly into the bed frame to ensure the mattress won’t slip and slide and to prevent falls.

Let’s take a look at some of the bunk bed mattress sizes and variations you can find.

Bunk Bed Mattress Sizes Chart

Twin Bunk Bed Mattress Size

Most bunk beds hold twin size mattresses. It measures 75 inches long and 38 inches wide and works on both top and bottom bunk beds. One of the great parts about twin size bunk beds is they fit in basically any bedroom— all you need is vertical space to fit the height of the bunk bed.

Twin XL Bunk Bed Mattress Size

Twin XL bunk bed mattresses are slightly longer, measuring 80 by 38 inches. The extra 5 inches of length in a twin XL compared to a twin makes it more suitable for growing teens and adults. Twin XL mattresses fit both the top and bottom bunk and work well in dorms, studios, and small bedrooms.

Full Bunk Bed Mattress Size

Full, or double, bunk bed mattresses measure 75 by 54 inches. While full mattresses are typically used on the bottom bunk, people can use them for the top bunk as well. A full-size mattress works best for single sleepers. They can technically fit two people in case there’s limited space, but they are not comfortable as a consistent sleep situation for two people.

Full XL Bunk Bed Mattress Size

Full XL bunk bed mattresses are 80 inches long and 54 inches wide and work well for tall, single sleepers. Full XL mattresses can be both a top and bottom bunk, but it’s unlikely you’ll find a mattress larger than a full XL on a top bunk.

Queen Bunk Bed Mattress Size

While rare, it’s possible to find a bunk bed with a queen bottom bunk and a twin or twin XL top bunk. Queen bunk bed mattresses measure 80 by 60 inches and fit in most master bedrooms. Queen mattresses fit two people and the top bunk typically fits one, sleeping three people total.

King Bunk Bed Mattress Size

King bunk bed mattresses are another rare bunk bed size since they require a large master bedroom, but most families with a large master bedroom don’t want a bunk bed. King mattresses measure 80 by 76 inches and are for the bottom bunk only, while the top bunk will likely be a twin or twin XL. They work well for three people, with two people sleeping on the bottom bunk and one person sleeping on the top bunk.

Consider Mattress Thickness

When shopping for bunk bed mattresses, keep in mind the mattress’s thickness to ensure your top bunk is safe to sleep on.

Top bunks have guard rails to protect a sleeper from falling and injuring themselves at night. So, if your top bunk’s mattress is too thick, it might end up taller than the guard rails, leaving the sleeper at risk of falling and getting hurt. Additionally, the thicker the top bunk’s mattress is, the less clearance there will be between the sleeper and the ceiling.

Ideally, choose a 4 to 6-inch thick mattress for your top bunk. Not only will a thinner mattress fit within the guard rails, but it will be easier to get in and out of the top bunk, make the bed, and remove and replace bedding for laundry day.

For the bottom bunk mattress, there’s little to worry about and few safety guidelines—bottom bunks have similar guidelines to regular mattresses and bed frames. You can choose any mattress thickness for your bottom bunk.

Bunk Bed Variations

Beyond different mattress sizes, bunk beds come in various dimensions. These different shapes and forms can accommodate unique needs and living spaces.

Standard

The most common bunk bed variation is the standard bunk bed, with two beds on top of each other. Typically, standard bunk beds have two twin mattresses, but they can have any of the other sizes previously mentioned, such as a twin over full, full over full, or twin over queen.

Triple

Triple bunk beds are three bunks stacked on top of each other. They typically exclusively fit twin beds and require a tall ceiling to use since the beds are between 75 to 82 inches tall.

Triple Loft

Triple loft bunk beds have two top bunks connected at a 90-degree angle, and one bottom bunk underneath one of the two top bunks. The open space underneath the second top bunk leaves space for a desk or a couch. Due to the shape of triple loft bunk beds, they work best in the corner of a bedroom.

Shorty

Shorty bunk beds are a low profile version of a standard bunk bed, measuring about 50 to 55 inches tall. A shorty bunk bed reduces the chance of injury in case someone falls out of the top bunk, though it doesn’t eliminate the risk. It also works well if you have limited ceiling space but still want a bunk bed.

Trundle

Bunk beds with a trundle bed attached are similar to standard bunk beds, only they have a sliding mattress underneath the bottom bunk. Trundle beds are useful when you’re trying to sleep three people but have limited space.

L-Shaped

L-shaped bunk beds have two bunks, but instead of being perfectly stacked, they’re perpendicular to each other. The bottom bunk is vertical, but the top bunk is horizontal. L-shaped bunk beds typically have more storage space than a standard bunk bed, though they do take up more space due to their perpendicular shape.

Futon

Futon bunk beds have a top bunk, but rather than a bottom bunk, there’s a futon in its place.  During the day, the futon is a couch, and at night, you can flatten it into a usable mattress. Futon mattresses are often thinner than standard mattresses and typically come in full size dimensions.

This couch-bed duo is good for dorm rooms or small apartments where you need to maximize your living space as much as possible.

FAQs

How tall are bunk beds?

There’s no standard bunk bed height, but they’re usually about 65 inches tall. Extra tall bunk beds are upwards of 75 to 82 inches, while short bunk beds are around 50 to 55 inches tall.

The right bunk bed height for your home depends on your ceiling height. There should be between 33 to 38 inches of clearance between the top bunk and the ceiling so a person can sit upright.

What’s the difference between loft beds and bunk beds?

Loft beds are similar to bunk beds since they both have an elevated bed, however, loft beds lack the bottom bunk. Instead of a bed, standard loft beds have space for desks, couches, or toys. Loft beds work well for single people living in a small space such as a studio, apartment, or dorm.

Do bunk beds need box springs?

Box springs aren’t required for bunk beds because they’re too tall and, as we’ve noted, too tall of a bed is dangerous for top bunks. Also, a box spring only works for an innerspring mattress, and nowadays, most people prefer a latex, hybrid, or memory foam mattress.

Rather than adding a base to a bunk bed, most bunk beds have slats or a bunkie board to support the mattress.

Can adults sleep in bunk beds?

There’s no age limit on bunk beds; however, adults should look for heavy-duty or high-capacity bunk beds if they want to sleep on a bunk bed regularly. Heavy-duty bunk beds have between a 250 to 800-pound weight capacity for the top bunk, while child-specific bunk beds only have a 150 to 220-pound weight capacity.

A larger bunk bed size is ideal for adult sleepers so they have enough space to stretch out and enough legroom for comfort. Also, a bunk bed should have enough overhead clearance so an adult can sit upright comfortably on the top bunk.

When sleeping on top bunks, keep in mind that top bunk mattresses are usually quite thin (4 to 6 inches). Thin mattresses likely thin foam comfort layers and won’t properly relieve an adult’s pressure points or cushion their spine and hips. An adult’s weight may also impact a thin mattress’s durability, causing any coils or foam to break down and require repairs or replacement.

Are bunk beds with stairs safer?

Most bunk beds have a small ladder attached to it so you can get to and from the top bunk easily. However, an increasing number of bunk beds have stairs in place of a ladder. Bunk beds with stairs and handrails make it easier and safer to access the top bunk, especially for young children.

Bunk beds with stairs take up more space and are generally pricier than bunk beds with ladders. However, the stairs sometimes double as storage drawers, so this can make up for the space they take up and the added cost.

What Bunk Bed Mattress Size is Right For You?

Bunk beds are ideal when you’re trying to maximize a small space, whether for an RV, a small apartment, or a kid’s bedroom. The best bunk bed mattress size for you depends on how many people are using the bed, their size, and their age.