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What Size Is a Bunk Bed Mattress? For Both Regular and Low

What Size Is a Bunk Bed Mattress? For Both Regular and Low

Do you consider owning a bunk bed but are unsure of the proper dimensions of each mattress? While most bunk bed mattresses use twin mattresses, some may require unique dimensions for custom pieces.

The size of a bunk bed mattress is similar to a standard bed mattress. For instance, a twin by twin bunk bed mattress measures 75 by 39 inches. However, it is lighter, thinner, and varies in size, with the lower bunk mattress being the heaviest.

According to April 22's correlation, sixty-one percent of Americans have used bunk beds in their lifetime. However, a survey by Nationwide's Children Hospital reveals about 36,000 cases of bunk bed accidents happening in a year.

Most of the accidents result from falling off beds. A lack of stability, carelessness, or the mattress slipping off the bed can cause falling. Getting a bunk bed mattress that is a perfect fit for your bed prevents mattress-related accidents.

brothers bedroom windowTypes Of Bunk Beds And Their Mattresses

Mattress measurements vary from one bunk bed type to another. Twin over twin beds, for instance, are smaller than Full bunk beds. Here are the types of bunk beds and their ideal mattress measurements.

Standard Bunk Bed

A standard bunk bed measures 79 by 42 inches for lower and upper bunks. It has a height of 63 to 65 inches, depending on the material used to build the bed.

The dimensions of the twin over twin bed are 75 inches* 39 inches. Note that the mattresses are smaller than the bed frame. The bed is suitable for kids around preschool and elementary school.

Twin XL beds are a different variation of the standard bed. The top bunk is twin-sized, while the bottom bunk is twin XL. The measurements for the bottom bunk are

The mattress dimensions ideal for Twin XL beds is 79 inches * 68 inches for the bottom bunk. However, the top bunk will use the standard twin mattress. These beds are suitable for two kids of different ages. The bottom bunk is the best fit for a teenager.

Triple Twin Bunk Bed

Triple twin bunk beds are fit for multiple roommates in a limited space. They are used in camps and are suitable for kids around the age of six. You do not have to worry about stability because the beds come from heavy material. Many companies prefer wood to support the weight.

Bed sizes for triple twin bunk beds usually vary according to the company. Sometimes, buyers ask for their customized size too. An example of such a bed on Amazon has dimensions of 78.25 by 79 by 74.25 inches. The mattress size that would fit this bed size is 75 by 39 inches.

Double/ Full Bunk Beds

These beds have the exact measurements as the lower bunk on the twin over full bunk beds. Both the top and bottom bunks are of equal sizes, and the height is 65 inches. They are suitable for two adults sharing a small room.

Combination With Queen And King Bunk Beds

These bunk beds are custom-made in many situations due to their low demand. Their design is that the top bunk is either twin or full-sized. The bottom, however, is king-size or queen-size.

The queen-size bottom bunk measurements are around 83 * 63 inches and can accommodate a mattress that is 80 * 60 inches in size. For the king-size, the measurements are 88 * 77 and can fit a mattress with dimensions of 80 * 76 inches.

They are suitable for parents who share rooms with their children.

Shorty Bunk Beds And Mattresses

The short bunk beds' design is ideal for kids. They are shorter than regular bunk beds and are up to 50 inches high. Also, they come from heavier and safer materials which ensure stability. They use twin or full mattresses similar to the ones for regular bunk beds.

Note that short bunk beds do not prevent accidents from happening. However, they reduce the amount of damage that might occur. It is due to the height of the bed being closer to the ground, lowering the impact.

One downside of these beds is that the little children find it easy to outgrow them, making them uneconomical.

Things To Consider When Choosing A Bunk Bed Mattress

Choosing the best bunk bed mattress for your rooms is not as easy as it may sound. Even though you do not need particular types of mattresses, here are some things you need to look out for;

Bed Size

You need to know the measurements of both the top and bottom bunks before purchasing a mattress. You want to avoid a larger mattress because they can cause accidents. Similarly, smaller mattresses could easily slip off the beds.

Even though most beds are compatible with twin and twin XL mattresses, it doesn't mean that it is the case for you. Especially if your bed is custom made. To be safe, measure the inside of the bunk bed and have the measurements while searching for a mattress.


Even though most bunk bed users outgrow their beds after a short while, buying a durable mattress is essential. You want to buy a mattress that will last for more than five years without developing dips, sags, and shedding.

For this reason, you should avoid innerspring mattresses as they are prone to sagging.


The space between the lower and upper bunks will be limited if the mattress is too thick. Choosing a thick mattress to support your weight and thin enough to allow movement is essential.


Generally, bunk bed mattresses should not be too heavy. However, the lower bunk mattress should weigh more than the upper bunk. The reason is to shift the gravitational center of the bed lower to increase stability and avoid accidents.

Similar post: Height of Bunk Beds- What is the Standard? 

Why Choose A Bunk Bed?

To Save Money

Buying bunk beds for your children's rooms will cut you the cost of buying two beds. Siblings can share a room and a single bunk bed. It allows you to save money since it is economical.

To Get More Space

Bunk beds are the best option for a home that wants to economize space. Instead of having two beds in a room, you could purchase a single bunk bed. This bed will fit in one of the room's corners, therefore allowing you to introduce more furniture.

For Adjustability

If not in use, you could separate the upper and lower half of the bunk bed to get two beds. It comes in handy when moving your children to different rooms.

They Are Cool

Sharing a room with your siblings can be so cool. I mean, who doesn't like a never-ending sleepover? They also come in many different colors and shapes that beautify the room.

mattress bedThey Are Customizable

Bunk beds are available in different shapes, sizes, and colors. However, you can still order a customized bunk bed for a clean-cut design and finish. Therefore, you can get your kids a bed that looks like a castle.

Also, you can order a bed that has specific features to protect your children from injuries. For example, a ladder will help your child climb up and down the bed easily.

More like this: What Is A Plush Mattress? How Is it Different? [GUIDE]


When purchasing mattresses for bunk beds, we recommend those with a height of between 6 and 12 inches. It ensures enough space for movement when lying on the bottom bunk. Also, check the mattress weight to get the suitable capacity for the beds for improved comfort.

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