Cot bed vs toddler bed: which is better?
Short answer: They do different jobs. A cot bed is a cot with removable sides and ends that converts into a toddler bed, most often taking a 140 x 70cm mattress. A toddler bed is a low bed sized for a cot-bed mattress (often 140 x 70cm), usually with side guards, for children moving out of a cot. Choose by your baby's stage, your space and how long you want to use it.
Cot bed
Used as a cot from birth, then as a toddler bed once your child is climbing or ready for a bed.
- Check the mattress size listed for the frame. 140 x 70cm is common, but not universal.
- Keep every conversion panel, bolt and instruction sheet for the toddler-bed stage.
- Look at adjustable base heights, teething rails and any matching furniture.
Toddler bed
Used once your child has outgrown the cot or is climbing out of it. Many UK families switch between about 18 months and 3 years.
- Check the mattress size it takes and buy a mattress that fits snugly.
- Side guards help stop your child rolling out in the early weeks.
- A low height makes it easier to climb in and out on their own.
| Cot bed | Toddler bed | |
|---|---|---|
| Typical use | as a cot from birth, then as a toddler bed once your child is climbing or ready for a bed | once your child has outgrown the cot or is climbing out of it. Many UK families switch between about 18 months and 3 years |
What the guidance says
- Use a firm, flat, waterproof mattress in good condition, with no raised or cushioned edges, that fits the cot or Moses basket with no gaps.
- Keep the cot clear: no pillows, duvets, cot bumpers, loose blankets, soft toys, pods, nests, wedges or anything to keep your baby in place.
- Cots and travel cots: look for BS EN 716-1:2017.
- Mattresses: look for BS 7177:2008+A1:2011, and BS EN 16890:2017+A1:2021 for cot, travel cot and crib mattresses.
Related questions
How long can you use a cot bed?
As a cot from birth, then as a toddler bed once your child is climbing or ready for a bed.
How long can you use a toddler bed?
Once your child has outgrown the cot or is climbing out of it. Many UK families switch between about 18 months and 3 years.
Shop at Baby Kingdom
- Mathy By Bols Madavin Adjustable Baby Cot 60 x 120cm
- Nika Cot Bed - Oak & White
- Grace Cot Bed, Cot Top Changer + Fibre Mattress - Warm Grey
- Tutti Bambini Malmo Cot Bed, Cot Top Changer and Mattress Bundle - Honey Oak
Check each product page for its exact dimensions, mattress size, age and weight limits and safety standards.
More advice
How do I choose a travel cot?Do I need a cot or just a bedside crib?Can a 4 month old still sleep in a Moses basket?Are baby hammocks safe?Summer sleep safety quizBritish Standards for baby sleep products explainedAll safe sleep and sleep spaces advice →
Sources
- The Lullaby Trust: Baby mattresses and bedding (accessed 2026-10-21)
- NHS: Sudden infant death syndrome (SIDS) (accessed 2026-10-21)
General information only, not medical advice. Always follow your product's instructions. If you are worried about your baby, contact your GP, health visitor or 111. In an emergency, call 999.