Last updated: September 2026.
If the room takes a single, buy the single. A standard South African single at 92 x 188cm bought when your child leaves the cot is still the correct mattress when they are sixteen. Our recommendation is the Active Foam Single at R3,399, our firmest build at 50 density. The 140 x 70cm cot bed size is the right answer in exactly two situations: the frame you already own is a 140 x 70, or the room genuinely cannot take a single.
That is the decision. The rest of this is the working, because roughly a million South African families reach this point every year, somewhere between eighteen months and three years old, and it is the single most common question our sales team takes on a Saturday morning.
The arithmetic nobody in this trade publishes
The furniture industry has a rule for when a bed is outgrown: when the child's head and feet come within ten centimetres of the ends. That gives you a usable height of the mattress length minus twenty centimetres, and once you have that, the whole decision becomes arithmetic instead of opinion.
| Mattress | Length | Comfortable up to a child of | Which is roughly |
|---|---|---|---|
| Toddler / cot bed | 140cm | 120cm tall | about six to seven years old |
| Single | 188cm | 168cm tall | about fourteen to sixteen, and many adults |
| Three Quarter | 188cm | 168cm tall | same length as a single, 15cm wider |
| Single extra length | 200cm | 180cm tall | a tall teenager or an adult |
Now put real growth against it. These are median heights, so your child will be above or below and both are normal.
| Age | Median height | Still fits a 140cm toddler bed? |
|---|---|---|
| 2 | 86 to 87cm | Yes, with 53cm to spare |
| 3 | 94 to 96cm | Yes |
| 4 | 102 to 104cm | Yes |
| 5 | 109 to 111cm | Yes, but the spare room is shrinking |
| 6 to 7 | about 116 to 122cm | This is where it runs out |
| 8 | 127 to 130cm | No |
A 140 x 70 bought at two is outgrown at about six or seven. A single bought at two is outgrown somewhere in the mid teens. That is the entire buy once argument, and it is not a slogan, it is two numbers and a ruler.
Active Foam Single, R3,399 50 density, our firmest, 365 night trial
The South African sizes, for reference
Worth having in one place, because the Three Quarter is a genuinely South African size that confuses anyone working off an overseas guide.
| South African size | Dimensions | Our price |
|---|---|---|
| Toddler / cot bed | 140 x 70cm | R1,699 Comfort Foam, the only mattress we cut at this size |
| Single | 188 x 92cm | R3,399 Active Foam, 50 density, our firmest. R2,399 in Comfort Foam |
| Three Quarter | 188 x 107cm | R3,799 Active Foam. R2,799 Comfort Foam |
| Double | 188 x 137cm | R4,299 Active Foam |
| Single extra length | 200 x 92cm | Not cut in Active Foam. Revive Single Extra Length R5,879 |
And the sizes that are not these, which is where most of the confusion starts: a standard South African cot takes 56 x 118cm and a large cot takes 66 x 132cm. European cots are usually 60 x 120cm. None of those is a 140 x 70. Measure the frame, not the old mattress.
The four situations, and what to buy in each
| Your situation | Buy | Price |
|---|---|---|
| Leaving the cot, the room takes a normal bed | Active Foam Single, 50 density, our firmest | R3,399 |
| You already own a 140 x 70 cot bed or floor bed frame | Comfort Foam Toddler 140 x 70, the only mattress we cut at that size | R1,699 |
| You read to them lying down and want the room | Active Foam Three Quarter, 107cm wide | R3,799 |
| A second bed, an older child, budget is tight | Comfort Foam Single | R2,399 |
Why the small size keeps getting bought anyway
Because the frame comes first. A parent buys a cot bed, or a floor bed, or inherits one from a cousin, and the frame dictates the mattress. That is completely reasonable and it is why we cut the 140 x 70 at all.
What we would push back on is buying the small size when the room has the space, purely because it feels like the correct toddler step. The bed frame can be a toddler step. The mattress does not need to be, and that is where the money goes twice.
The money, over ten years
A R745 toddler pad is genuinely cheap on the day, and we are not going to pretend otherwise. It is also outgrown around six, at which point you buy a single. Then, if it was a low density foam, you buy another single around twelve. Three purchases.
A R3,399 Active Foam Single bought at two is under thirty rand a month across ten years, carries a ten year warranty, and is one purchase. It is not the cheaper option this month. It is the cheaper option by the time they are in high school.
Get a protector, and here is why with numbers
Accidents are not a footnote at this age, they are the design constraint. About twenty percent of children still wet the bed at five, around ten percent at seven, and roughly one in twenty at ten. By fifteen it is under one percent. So somewhere in the first few years of that mattress, it is going to happen.
Our cover is quilted and it does not unzip, so it cannot go in the machine. It is washable in place, spot clean with warm water and mild soap and dry it fully before making the bed. A waterproof protector on top is the layer that should take the accident, and it costs a fraction of the mattress underneath it.
If it is going on the floor or in a low frame
Plenty of South African families do the cot to bed move straight onto a Montessori style floor bed, and eighteen months to three years is exactly the window for it. Two practical things that matter more than the aesthetics.
Keep the mattress low enough that the frame rail still stands proud of it. The rail is the thing that stops a sleeping child rolling out. Once the mattress sits level with the rail, the rail is decoration and you have put the fall back.
Let it breathe. A mattress flat on a tiled or wooden floor has no airflow underneath, and in a room above about sixty percent humidity mould can begin within two to four weeks. That is a real issue on the KwaZulu-Natal and Cape coasts. Use a slatted frame, or stand the mattress against a wall for an hour once a week. Inland the problem inverts: a Johannesburg or Pretoria tiled floor in winter is cold and pulls that cold up all night. A frame with legs solves both.
The full guide is here: Montessori floor bed mattress, South Africa.
The age rule, before anything else. A mattress on or near the floor is for a child of 12 months and older. Under 12 months the American Academy of Pediatrics, Red Nose in Australia and the Lullaby Trust in the United Kingdom all say the same thing: a cot, a bassinet or a play yard, and nothing else. Montessori writers such as Simone Davies suggest a floor bed from crawling, about nine months. We follow the safe sleep bodies, not the furniture trend, so we will not sell you a floor mattress for a baby under one. Between 12 and 18 months it can work, but only in a properly child proofed room, and speak to your clinic sister first.
What we would actually put in the room
Same recommendation whichever route the frame pushes you down. The size decides it.
| If this is you | Buy | Price |
|---|---|---|
| Child is leaving the cot and the room takes a normal bed | Active Foam Single. 50 density, our firmest build, 92 x 188cm | R3,399 |
| The frame you already own is a 140 x 70 | Comfort Foam Toddler 140 x 70, the only mattress we cut at that size | R1,699 |
| You read to them lying down and want the room | Active Foam Three Quarter, 107 x 188cm | R3,799 |
| A second bed, an older child, budget is tight | Comfort Foam Single | R2,399 |
| The frame measures 200cm long | Revive Single Extra Length | R5,879 |
If you only read one line: for a child's first proper bed, the Active Foam Single at R3,399 is the one we recommend and the one we would put in our own children's rooms. It is a 50 density foam, which is above every band the international children's mattress guides call ideal, it is our firmest build, and at 188cm it is still the right length when they are sixteen.
What comes with it. SABS approved foam and a Confidence in Textiles cover fabric, which are the two marks that mean something in South Africa. A 365 night trial, which is a full year, against the 100 nights the big bed chains offer and the nothing at all a furniture maker offers on a mattress. A 10 year warranty. 30 day money back. Free delivery anywhere in the country, typically three to seven working days from our factory in Bloemfontein.
See every size and price toddler from R1,699, single from R2,399
Questions we get asked
Cot bed size or straight to a single?
If the room takes a single, buy the single. A single at 188cm is comfortable for a child up to about 168cm tall, which is mid teens for most South Africans. The 140 x 70 cot bed size is the right call only when the frame you already own is a 140 x 70, or the room genuinely cannot take a single.
When does a child outgrow a 140 x 70 toddler bed?
When their head and feet come within ten centimetres of the ends, which on a 140cm mattress means a child of about 120cm tall. That is roughly six to seven years old at median growth. An eight year old at 127 to 130cm has already outgrown it.
What are the South African bed sizes?
Single 188 x 92cm, Three Quarter 188 x 107cm, Double 188 x 137cm, Queen 190 x 152cm, King 200 x 183cm. Most sizes are also available in extra length at 200cm. The Three Quarter is a distinctly South African size and it is the quiet favourite for a child who likes a parent to lie down at bedtime.
What size is a South African cot mattress?
A standard cot takes 56 x 118cm and a large cot takes 66 x 132cm. European cots are usually 60 x 120cm. None of those are the same as a 140 x 70 toddler or floor bed. Measure the frame, not the old mattress.
Do I need a mattress protector?
Yes, at this age. About twenty percent of children still wet the bed at five, around ten percent at seven, and roughly one in twenty at ten. A waterproof protector is far cheaper than a mattress and our cover does not unzip, so the protector is the layer that takes the accident.
Is a Three Quarter worth the extra?
If you read to your child lying down, yes. It is the same 188cm length as a single and fifteen centimetres wider, at R3,799 against R3,399. Plenty of parents decide that is the entire point of the bed.
How long does delivery take?
Free anywhere in South Africa, usually three to seven working days from our factory in Bloemfontein. Most of our kids mattress orders go to provinces with no bed factory at all.
Can we use a cot mattress on a toddler bed?
Only if it is genuinely the right size for that frame, and most are not. Cot mattresses run 56 x 118 or 66 x 132. A toddler or floor bed frame is usually 140 x 70. A gap at the side is somewhere a small arm or leg can go.
What if we get it wrong?
365 nights to decide, and 30 days for a straight money back if you change your mind early. A year is not a marketing number on a child mattress, it is the only sensible window to judge one.
Do you make a cot mattress?
No, and we would not sell you a floor mattress for a baby under one year old either. Buy a proper cot mattress sized to your cot from a cot specialist and come back to us when the child moves out of it.
Sleep better. 365 night trial. 10 year warranty. 30 day money back guarantee.
Written by the Mr Mattress team in Bloemfontein. We make the mattresses we write about. Growth figures are WHO and CDC median heights. Bedwetting prevalence from healthdirect and the American Academy of Pediatrics. South African bed sizes cross checked against four South African retailers in September 2026.