When should I buy a cot sheet?
Short answer: Buy in time for when you will first use it: from birth. For newborn essentials, many parents order in the second trimester to allow for delivery and assembly.
- 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.
- If you use sheets and blankets, tuck them in firmly no higher than shoulder height. One blanket doubled over counts as two.
Related questions
What is a cot sheet?
A fitted sheet sized to the cot mattress.
Shop at Baby Kingdom
- Cot Bed Fitted Sheets 2pk
- Cloud Bedside Crib + 2 White Crib Fitted Sheets Bundle - Grey
- Bedside Crib Fitted Sheets 2pk
- Cloud Bedside Crib + 2 White Crib Fitted Sheets Bundle - Oatmeal
Check each product page for its exact dimensions, mattress size, age and weight limits and safety standards.
More advice
Can I swaddle a 9 month old?Are sleeping bags with sleeves safe?Can a 6 week old sleep with a blanket?Can I swaddle an 8 month old?Keeping your baby cool in a summer heatwaveGuide 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.