What size sheet fits a cot bed?
Short answer: Most cot bed sheets are 140 x 70cm to match the common cot bed mattress size. Check your mattress size first.
Here is the detail behind that answer, taken from current UK guidance from the NHS and the Lullaby Trust.
Things to check
- Match the sheet size to the mattress (for example 120 x 60cm or 140 x 70cm).
- Fitted sheets should sit tight and flat, with no loose fabric.
- Buy at least two or three for night-time changes.
What the guidance says
- The Lullaby Trust says a baby needs just two items in their cot: a firm, flat, waterproof mattress and lightweight bedding.
- 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.
Related questions
What is a cot sheet?
A fitted sheet sized to the cot mattress.
Shop at Baby Kingdom
- Crib Fitted Sheets – 2 Pack
- Muslin Fitted Sheet 140cm x 70cm - Berry Stripe
- Cot Fitted Sheets 2pk
- Snurk Furry Friends Fitted Cot Sheet
Check each product page for its exact dimensions, mattress size, age and weight limits and safety standards.
More advice
What tog sleeping bag does my baby need?Can a 2 year old sleep in a sleeping bag?Safe swaddling: what UK guidance saysCan a 4 month old sleep in a sleeping bag?Guide to cot bedding sets: what to look forGuide to swaddles & blankets: what to look forAll baby bedding and sleeping bags advice →
Sources
- The Lullaby Trust: Safer sleep advice (accessed 2026-10-21)
- 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.