What mattress does a crib need?
Short answer: 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. Use the size your frame lists.
- Use a mattress made to fit that crib exactly.
- If it rocks or glides, check there is a lock and use it for sleep where the instructions say to.
- Check the weight and stage limits.
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.
- The Lullaby Trust says your baby's head should sink no more than a few millimetres into the mattress.
- Mattresses: look for BS 7177:2008+A1:2011, and BS EN 16890:2017+A1:2021 for cot, travel cot and crib mattresses.
Related questions
What is a crib?
A small free-standing baby bed, sometimes with a rocking or gliding action, sized between a Moses basket and a cot.
Shop at Baby Kingdom
- Cloud Bedside Crib - Grey
- CoZee Sense Bedside Crib
- Bedside Crib Starter Pack
- Cloud Bedside Crib - Nutmeg
Check each product page for its exact dimensions, mattress size, age and weight limits and safety standards.
More advice
Can an 11 month old sleep in a travel cot?Can a 6 week old sleep in a cot?Can a 3 year old sleep with a soft toy?What should I put in a Moses basket?Travel cots buying guide for UK parentsWhich cot bed suits your nursery?All safe sleep and sleep spaces advice →
Sources
- The Lullaby Trust: Baby mattresses and bedding (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.