Bunk Bed Mattresses

Why choose a bunk bed mattress?

A bunk bed mattress needs to combine a secure fit with practical comfort for the person using it. The right choice can help you make better use of a shared or compact bedroom while meeting the requirements of the bed frame.

• Children's rooms: Choose an age-appropriate firmness and construction for regular use.

• Top bunks: Low-profile mattresses help preserve the effective height of the safety barrier.

• Bottom bunks: You may have more flexibility around depth, subject to the frame specification.

• Guest rooms: Bunk beds can provide two sleeping spaces without taking up the floor area of two separate beds.

• Easy bed changes: A lighter mattress can be easier to lift when changing sheets on a bunk.

How to choose the right bunk bed mattress

Start with size and depth. Many UK bunk beds use a standard single mattress measuring 90 x 190cm, but you should measure the sleeping platform and check the manufacturer's instructions rather than assuming every frame takes the same size.

Depth is especially important on the top bunk. A mattress that is too deep raises the sleeping surface and reduces the usable height of the guard rail. Current British Standard BS EN 747-1:2024 covers safety requirements for bunk and high beds, including protective barriers and instructions for use. 

Many manufacturers specify maximum mattress depths somewhere around 12–18cm, but this is not one universal legal depth limit. Always follow the maximum stated for your particular frame.

Next, consider who will sleep on each bunk. Younger sleepers may experience firmness differently from heavier teenagers, so aim for comfortable, age-appropriate support rather than automatically choosing the firmest mattress available. Medium or medium-firm options can provide a balanced starting point, but suitability varies by sleeper and product.

Also compare mattress weight, breathability and cover materials. A lighter design can make top-bunk sheet changes easier, while breathable comfort layers may suit warmer bedrooms.

Finally, check applicable safety information, mattress care instructions and warranty details on the individual product page.

Why shop at MattressNextDay?

Next day delivery - Free next-day delivery is available on eligible in-stock mattresses across the UK mainland.

Lowest price promise - Use our Lowest Price Promise for extra reassurance when comparing bunk bed mattresses.

Old mattress removal - If you're replacing an existing mattress, add old mattress removal when you order.

Excellent reviews - Read verified customer feedback to help you compare before making your decision.

Award-winning retailer - Buy from a three-time NBF Online Bed Retailer of the Year.

British-designed quality - Explore British-designed mattresses made with carefully selected materials.

Need help choosing your next mattress?

Tell us how you sleep, the firmness you prefer and what you would like to spend. MattressFinder™ can narrow the choice and help you compare suitable mattress options. Find your perfect mattress.

Buying guidance for bunk bed mattresses

Choosing a mattress for bunk beds involves a few extra considerations beyond comfort. Mattress depth, who will use each sleeping level, and the mattress's construction all matter when finding an option that works safely with the frame.

Bunk bed safety regulations and maximum mattress thickness explained

A top-bunk mattress must leave enough of the safety barrier exposed above the sleeping surface. Using an overly deep mattress can reduce the effective guardrail height and increase the risk of someone rolling over it. UK safety guidance similarly stresses that mattress height needs to remain within the limits specified by the bed manufacturer where protective rails are involved.

Although many bunk-bed manufacturers set maximum mattress depths in the 12–18cm range, always treat the number printed on your particular frame or instructions as the limit. A 15cm mattress, for example, should not be used where the manufacturer specifies a 12cm maximum.

Government-backed guidance also advises that bunk and cabin beds are unsuitable for children under six.

Top bunk vs. bottom bunk mattress requirements

Never assume the bottom bunk automatically supports an adult. Check the manufacturer's maximum user weight for the individual sleeping level.

Choosing the right low-profile firmness for growing children

Low profile describes mattress depth, not firmness. A shallower bunk bed mattress can still be available in different comfort grades.

For growing children, choose a firmness that provides comfortable support without assuming that an extra-firm surface is always preferable. A child's size, usual sleeping position and personal preference all affect how a mattress feels.

Construction matters too. Foam can provide close cushioning in a relatively compact design, while suitable sprung mattresses offer a more responsive feel. Cooling fabrics or breathable layers can be useful in rooms that tend to feel warm, while products with specific material or textile certifications should clearly state those credentials in their individual specifications.

Delivery, recycling, and guarantees

Free next-day delivery to most locations - Need to set up a bunk bed quickly? Free next-day delivery is available across the UK mainland on eligible in-stock mattresses.

Free weekend delivery - Select a weekend delivery slot, if available, to make receiving your mattresses more convenient.

Choose a delivery date - Pick your preferred delivery date at checkout, where this option is available.

Learn more about our delivery and returns policies.

We make old mattress disposal easy for you

Just £39 to responsibly dispose of your old mattress - Add old mattress removal at checkout for £39 and MattressNextDay will collect your old mattress when your new one arrives.

100% of your mattress is reused and recycled - Collected mattresses are broken down into their core components so the materials can be repurposed, with 100% reused and recycled.

A greener way to get rid of your old mattress - Combine delivery and disposal rather than arranging a separate collection for your old mattress.

Find a great value bunk bed mattress

Buying mattresses for both bunks? Compare the total cost across suitable sizes, depths and comfort grades before ordering. Shop mattress sale.

Ask the expert about bunk bed mattresses

Choosing a mattress is easier when you know what to compare. Our product experts answer common questions about bunk bed mattresses, including size, protection, maintenance, warranties, and delivery.

Martin Seeley, Product Expert at MattressNextDay, answers questions about bunk bed mattresses.

What size is a standard bunk bed mattress in the UK?

Many UK bunk beds are designed for a standard single mattress measuring 90 x 190cm, although this should never be assumed from the words "bunk bed" alone.

Some children's bunks, cabin beds and imported bed frames use different dimensions. Measure the actual mattress platform and check the measurements supplied by the bed manufacturer before ordering. The mattress should fit securely without leaving inappropriate spaces around the sides or ends.

Can I use a normal single mattress on a bunk bed?

Only if its dimensions, depth and construction meet the requirements stated by the bunk-bed manufacturer.

A standard single mattress may have the correct 90 x 190cm footprint but still be too deep for the frame, particularly on an upper bunk. Some everyday mattresses are considerably deeper than purpose-designed low-profile models.

Check all three dimensions before buying: length, width and depth.

What type of bed base can a bunk bed mattress go on?

Most bunk beds use slats or another built-in support platform, but requirements vary between frames and mattresses.

Check the mattress manufacturer's base guidance, including any requirements around maximum slat spacing. Memory foam and pocket sprung mattresses can have different support needs, and placing a mattress on an unsuitable base could affect how it feels or wears.

The bunk frame itself should also be assembled and used according to its manufacturer's instructions.

Should I buy both bunk bed mattresses at the same time?

You do not necessarily need to replace both mattresses together if one is still in suitable condition, fits correctly and meets the requirements of the frame.

However, buying both at once can make it easier to coordinate sizes, depths and comfort levels when setting up a new bunk bed. If you are shopping for two mattresses, compare the combined price and check whether any current promotions apply rather than assuming there is automatically a two-mattress discount.

Do both bunk mattresses need to be the same firmness?

No. If the mattresses are compatible with the frame, each sleeper can have a comfort grade that better suits their preference.

For example, siblings of different ages or sizes may find different firmness levels comfortable. The key is to make sure both mattresses meet the dimensional and depth requirements for the bunk they will occupy.

Do I need special sheets for a bunk bed mattress?

Usually, you need sheets that match the actual mattress dimensions and depth rather than bedding specifically labelled for bunk beds.

Low-profile mattresses can be shallower than standard mattresses, so very deep fitted sheets may have excess fabric. Measure the mattress and check the fitted-sheet pocket depth for a neater fit.

For an upper bunk, a well-fitting fitted sheet can also make changing the bed easier than dealing with unnecessary loose material.

Should I use a mattress protector on a child's bunk bed?

A mattress protector can be useful for helping protect against spills, accidents and everyday marks, particularly on children's beds.

Choose one that matches the mattress dimensions and does not significantly alter the overall mattress height. This is especially important on a top bunk, where adding thick toppers or layers can raise the sleeping surface relative to the guard rail.

Always keep the complete sleeping setup within the bed manufacturer's requirements.

Can I add a mattress topper to a bunk bed mattress?

Be careful when adding a mattress topper to an upper bunk because it increases the total sleeping-surface height.

Even if the mattress itself is within the permitted depth, adding several centimetres of cushioning can reduce the effective height of the safety barrier. Safety guidance warns that additional mattress height can reduce the effectiveness of bed rails.

Check the bed manufacturer's instructions before adding any topper, mattress pad or other substantial layer.

How often should I replace a bunk bed mattress?

There is no separate replacement schedule simply because a mattress is used on a bunk bed.

Check it periodically for visible damage, permanent sagging, uncomfortable areas or changes around the edges. Children's needs can also change as they grow, so it is worth reassessing comfort and suitability rather than relying only on the mattress's age.

Follow the manufacturer's care instructions, including rotation guidance where applicable.

Can I get free next-day delivery on bunk bed mattresses?

Free next-day delivery is available on eligible in-stock mattresses across the UK mainland. Availability depends on the individual bunk bed mattress you choose.

If you're ordering two mattresses for the same bunk bed, check the delivery information for both products so you know whether they can arrive together. Weekend delivery may also be available on selected orders.