We’re all familiar with standard mattress sizes, but many of us don’t know that there are many larger mattresses out there. This is understandable, since oversized mattresses, named for their larger than standard size, are sold by very few vendors. Oversized mattresses can be anywhere from 4to 68 inches larger than a king sized mattress, and often require a larger bedroom. They are therefore not in high demand.

Even though oversized mattresses aren’t as easy to buy as their standard counterparts, they have a great deal to offer for people who co-sleep with other adults or children. This may also be the case for people who need a large amount of space, due to size or movement during sleep.

In fact, with almost 60% of dog owners now sharing their bed with the family dog, pet owners may be interested in an oversized mattress that allows them to sleep comfortably with their furry companions.

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Oversized Mattress Sizes Explained

Oversized Mattress SizeDimensions (Width x Length)Recommended Room DimensionsAverage Price
Alaskan King108” x 108”14′ x 14′$2,500 – $6,000
Alberta King96” x 96”13′ x 13′$5,000
Wyoming King84” x 84”12′ x 12′$1,500 – $4,000
Texas King80” x 98”12′ x 14′$2,000 – $4,000
Family144” x 80” or 120” x 80”17′ x 12′$2,800 – $6,000
Family XL144” x 84”17′ x 12′$3,000 – $6,000

Alaskan King (108 x 108) – The most well-known of the oversized mattresses, this square shaped mattress is wide enough to accommodate families that co-sleep with more than one child, and long enough for tall sleepers that prefer to stretch out when they sleep. In fact, this is the longest oversized mattress size.

Alberta King (96 x 96) – At just one foot smaller than the Alaskan king, this square shaped mattress is a good choice for people that want the same shape and benefits of an Alaskan king, but need a mattress that will fit into a slightly smaller room. It is also the least common oversized mattress size.

Wyoming King (84 x 84) – The smallest of the square shaped oversized mattress sizes, the Wyoming king is likely to comfortably fit a couple that prefers to co-sleep with a single small child. Alternatively, it could give increased room to two adult sleepers. This is the only oversized mattress size that may potentially fit comfortably within the average master bedroom.

Texas King (80 x 98) – This rectangular mattress is well-suited to those who may be looking for a mattress that is slightly wider than the standard king, but significantly longer. It is well-suited for tall people, those who like to stretch out, or people who prefer to sleep with a pet at the foot of the bed.

Family (144 x 80 or 120 x 80) – Wider than it is long, this rectangular mattress can accommodate multiple sleepers, plus pets. However, while the family size mattress is normally twice the width of a king size mattress, it is also 4 inches shorter. This mattress size may also vary in width, depending on which retailer it is bought from. This mattress size will only fit in a very large room.

Family XL (144 x 84) – This is the biggest mattress size by far, and is the size of two California king mattresses, side by side. It is meant to accommodate multiple adults, as well as pets. The family XL is rectangular, and requires a very large room. This mattress can be supported with two California king size box springs, or a single, extra wide box spring can be used.

Custom – Custom mattresses are made to order, according to the individual specifications of the purchaser. These mattresses tend to have irregular shapes and sizes. They may work for people that need to fit their beds into irregularly shaped spaces, such as an RV or a boat. It also suits people that prefer non-standard shapes, such as circles, hearts, or half-moons. Cost tends to vary based on size, with larger mattresses being more expensive.

How to Choose an Oversized Mattress Size

With so many different mattress sizes to choose from, selecting the right one for your needs can be daunting. Fortunately, deciding which size works best for your individual situation and sleeping style can be simplified by paying attention to a few factors.

Bedroom Dimensions

It is important to determine whether you can comfortably move around in the bedroom once your mattress is inside. Be sure to include your bedroom furniture, such as a dresser or vanity, into these figures, as well. A good rule of thumb is to ensure you have at least 2 feet of space on either side.

Ease of Transport

Larger mattresses can be difficult to fit through doorways. It can also be hard to maneuver them around staircases. Take measurements, if necessary, to be sure your mattress will be able to make it all the way into your home. You should also consider how many people will be needed to carry the mattress.

Accessories & Foundations

Oversized mattress accessories, such as sheets and mattress pads, can be hard to find. Many times, they need to be custom made, because most companies don’t keep these sizes in stock. The foundation that an oversized mattress sits on needs to be carefully chosen, as well, because these mattresses are all too large to sit on a single king size box frame.


Oversized mattresses cost significantly more than standard sizes, ranging from $1,500 all the way up to $6,000, so careful consideration needs to go into the decision to buy one. You should also remember that more money will need to be spent on accessories and a foundation. Retailers often offer financing plans.

Sleeping Partners

The number of sleepers sharing a bed is a necessary factor when deciding on an oversized mattress. It is important to consider each person’s sleeping position, how they orient themselves on a mattress, and their general size. It’s also a good idea to think about any pets that may sleep on the mattress, and where they lay on the bed.

Sleeper Height

A person’s height has a direct influence on mattress choice. While a smaller person can choose a mattress with less length, a taller person may opt for something considerably longer. When considering height, be sure to think about how many inches may need to be added for people who prefer to stretch out.


Versatility should be considered when buying an oversized mattress. You should determine how many sleepers it can accomodate, and how many sleep positions are viable. You might also wish to think about how long the bed will be used, and whether there are any growing children whose future size will need to be taken into account.

Sleeping Position

If you prefer to stretch out, it would be wise to note just how much more space than your standing height you may take up. Additionally, it is wise to think about what your preferred sleeping angle is. For example, if you sleep diagonally, mattress width may be more important to you than height.

Frequently Asked Questions About Oversized Mattresses

Where Can I Buy an Oversized Mattress?

Oversized mattresses are rarely seen in brick-and-mortar stores, but it’s possible to find them locally at retailers that sell custom beds. Additionally, by searching in your web browser for the specific mattress size that you’re interested in, you can find online vendors that sell the particular mattress type you’re looking for. Online custom bed retailers may also have oversized mattresses available.

Where Can I Find Sheets and Other Accessories for Oversized Beds?

Searching online for oversized bed accessories can give you a range of online stores to choose from. One thing to consider, though, is that oversized bed accessories are often a custom order, and you may have to wait longer than usual on delivery, since companies don’t typically keep oversized mattress accessories in stock. Often, though, the store that you purchase an oversized mattress from will have accessories that are made specifically for the mattress you choose.

What is the Biggest Bed Size?

It is often said that the Alaskan King, sized at 108” x 108”, is the biggest bed, and it certainly is the longest, with a generous width to go with it. However, the widest bed out there is the Family XL, which is a full 144” wide, but only 84” long. Therefore, when looking for the biggest bed out there, it is important to consider whether length or width is the determining factor for you.

What Size Box Springs Should be Used with Oversized Mattresses?

Most often, the box spring can be bought at the same time as the mattress, which ensures a proper size. In rare cases, though, two standard size box springs can be set side by side underneath an oversized mattress and work equally well. One example of this is the family, which sports the same mattress size as two king size mattresses, set beside each other.

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