Single Mattresses

Firmness and support options in single mattresses

Is your child outgrowing their cot and ready for a big-kid bed? Measuring 92cm x 188cm, a standard Australian single mattress is the ideal first step, and it fits perfectly into most bunk beds. When you’re choosing one, it’s worth thinking about firmness before anything else. Medium firmness gives a growing body enough spinal support without the pressure discomfort that a very firm option can cause a lighter sleeper. On the other hand, going too soft can cause a lighter child to sink in too far, throwing their spine out of neutral alignment. If you’re buying a single for an adult guest room or occasional use, the same medium-firm logic tends to apply, as most adult-weight guidance assumes a heavier sleeper than a single mattress is really built for. If bedtime’s been a battle, start here.

If you want to compare firmness levels side by side, shop our full range of mattresses , and once you’ve settled on a size, browse our kids single beds to find a frame to match.

Single mattress sizing from bunk beds to guest rooms

A single mattress is the practical choice for smaller bedrooms under 9 square metres, where a larger bed would eat into the floor space needed to move around comfortably. It also suits guest rooms that only see occasional use and need to stay flexible the rest of the time.

For children up to around twelve years old, a single typically provides adequate sleeping width without feeling cramped. Once a child does start approaching 150cm in height, many families move to a king single at 107cm x 203cm, which buys a few extra years before a full-size upgrade is needed.

When it’s time for that next step, our beds range covers everything from king singles up to full-size frames.

Slat spacing and frame compatibility for single mattresses

If the mattress will sit on a slatted bed frame, choose a model where slats are no more than 7cm apart. Wider gaps reduce support under the mattress, and they can also void the manufacturer’s warranty if resulting sagging is traced back to the base. If you’re buying for a child or a lighter adult under 65kg, a medium or medium-soft single mattress balances cushioning and support without letting the sleeper sink too deeply into the surface. This matters more on a lighter frame, where there’s less body weight to compress the mattress evenly.

It’s also worth checking that the base itself is rated for the mattress type, since some foam and latex mattresses specify their own maximum slat spacing that can be stricter than the frame manufacturer’s general guidance. Getting the base and mattress compatible from the outset avoids a warranty dispute down the track.

Pair your new mattress with a matching bedhead to finish the look.

Frequently asked questions

What are the dimensions of a standard Australian single mattress?

A standard single mattress in Australia is 92cm wide by 188cm long. A king single measures 107cm wide by 203cm long, 15cm more in both directions.

How long does a single mattress typically last?

A quality single mattress lasts between 8 and 10 years with regular use. Innerspring mattresses may show reduced support after 7 years, while high-density foam and latex often perform well for 10 years or more.

What mattress type is best for bunk beds?

A mattress with a maximum depth of around 20cm to 22cm is generally recommended to maintain safe rail height on the top bunk. Memory foam and latex mattresses work well since they don’t need a spring system to stay supportive at slimmer profiles.

Can adults use a single mattress?

Yes, adults can use a single mattress comfortably if they sleep alone and the 92cm width suits their sleeping style. Side sleepers often find a double at 138cm x 188cm more comfortable as it gives more room to shift positions.

Do single mattresses need a box spring or base?

Most modern single mattresses work on a slatted timber base or platform bed and don’t require a box spring. Some foam and latex mattresses specify a maximum slat spacing of 7cm to maintain warranty coverage.