Travel cot and co-sleeper for baby: what's important?

For many families, a travel cot is the first bed that isn't permanently in the nursery – yet it's used for weeks at a time: at grandparents' houses, on holiday, or in the living room for a nap. That's precisely why it's worth seeing it as more than just an emergency bed. A co-sleeper, on the other hand, is the solution for the first few months, placed right next to the parents' bed. Both have clear safety requirements, and for both, the most important point is the same: the mattress. For infants, a mattress that is too soft, too thick, or too small is not a comfort issue, but a safety issue. This guide clarifies the criteria and shows what you should pay attention to when buying and in everyday use.

The short answer: A travel cot primarily needs a firm, flat, and precisely fitting mattress – a maximum height of 5 cm and no gap to the frame. The standard size is 60 × 120 cm; some models measure 70 × 100 cm. Co-sleepers are securely attached to the parents' bed and are suitable until about six months of age or until the child can sit up independently. In both beds, the rule is: let the baby sleep on their back, no pillows, no duvets, no cot bumpers – instead, use a sleeping bag. A travel cot is suitable for occasional nights, but it is not a substitute for a permanent bed.

Travel cot or co-sleeper – two different purposes

The two types of beds solve different problems. A co-sleeper is placed directly next to the parents' bed, usually with one open side, and is fixed to the bed frame. It allows for closeness during breastfeeding and comforting at night, without the child sleeping in the parents' bed. This setup is recommended for the first six months because the child particularly benefits from proximity during this time – but remains in its own safe sleeping space.

A travel cot, on the other hand, is a mobile solution: foldable, with textile sides and a collapsible base. It goes on holidays, to relatives, or to a holiday home. Some models have a height-adjustable insert, allowing them to serve as a raised sleeping surface in the first few months and later as a deeper bed.

Both beds have clear limitations. The co-sleeper should no longer be used once the child can sit up or pull themselves up independently – at that point, the open side becomes a risk. The travel cot is intended for occasional nights; the included insert is usually too thin and too soft for continuous use.

The mattress: the most important safety factor

For infants, a simple but absolute rule applies: the sleeping surface must be firm. A soft surface can cause the face to sink in, leading to insufficient air circulation. As a practical test, press firmly into the middle of the mattress with your flat hand – it should hardly give way and immediately return to its original shape. If an imprint remains, it is too soft.

Equally important is the precise fit. There must be no gap between the mattress and the frame where a child could get trapped. As a rule of thumb: if you can slide two fingers side by side between the mattress and the wall, the gap is too large. Therefore, always buy the mattress that matches the bed, not a universal size.

Regarding height: 4 to 6 cm is common and sufficient for travel cots. A thicker mattress reduces the distance to the top edge of the side walls, increasing the risk of an older child leaning out. Details on materials and test seals can be found under Baby Mattress and Safety.

Dimensions, construction, and what fits together

Please note that load capacity information varies from manufacturer to manufacturer. The operating manual for the specific model is always authoritative – not a general rule of thumb.

Safe sleep: the non-negotiable points

Regardless of which bed your child sleeps in, the same basic rules apply, consistently recommended by paediatricians. Firstly: back sleeping. Secondly: no pillows, no duvets, no cot bumpers, and no soft toys in the bed – instead, use a suitable sleeping bag that cannot slip over the head or restrict leg movement. Thirdly: a room temperature of around 16 to 18 °C and no overheating.

Fourthly: a smoke-free environment. Fifthly: the baby's own bed in the parents' bedroom for the first few months – exactly what a co-sleeper allows. These recommendations are based on extensive observational data for the prevention of sudden infant death syndrome. They are not a guarantee, but they measurably reduce the risk.

If you are unsure whether a specific sleeping situation is safe, discuss it with your paediatrician or a maternal and child health advisory service. Further practical tips for everyday life can be found under Sleeping with a Newborn.

Common mistakes with travel cots and co-sleepers

Mistake 1: Adding a thicker mattress. Many parents find the included insert too hard and add a softer or higher one. Both reduce safety: softer increases the risk of sinking in, higher reduces the distance to the top edge.

Mistake 2: Placing a blanket under the child. Additional layers between the child and mattress can shift and form folds. If the mattress seems too cold, a warmer sleeping bag helps, not an underlay.

Mistake 3: Using the travel cot as a permanent bed. For weeks or months, the thin insert is not an adequate sleeping surface. For everyday use at home, a proper cot with an 8 to 12 cm high mattress is required.

Mistake 4: Using the co-sleeper for too long. As soon as the child can sit up or turn over independently, the open side becomes a danger. At that point, it's time to switch to a closed cot.

Mistake 5: Not checking the assembly. Travel cots must click audibly into place. An incompletely locked frame can collapse. After each assembly, check all locks with gentle pressure from above.

Practical tips: making good use of the travel cot on the go

Test before you leave. Set up the bed completely at home once and let your child take one or two naps in it. A completely unfamiliar bed on the first evening of a holiday can be a barrier to falling asleep for many children.

Bring familiar items. The usual fitted sheet and sleeping bag provide familiar smells and feelings. This often works more effectively than any sleep aid.

Check the location. Do not place it directly next to heaters, windows, or curtains. Cords and strings should be out of reach. Pay attention to a consistent temperature – holiday homes often cool down significantly at night.

Blackout. In summer, it gets dark late and light early. A portable blackout blind or simply a dark cloth at the window significantly aids falling asleep – see Blackout Bedroom.

Maintain rhythm. Holidays can tempt you to later bedtimes. Most children can cope with one to two hours of deviation, but more often leads to overtiredness and poorer sleep. Our article on Children's Bedtimes provides guidance.

Frequently Asked Questions about Travel Cots and Co-Sleepers

What size is a travel cot mattress?

The most common size is 60 × 120 cm; some compact models measure 70 × 100 cm. It is crucial that the mattress fits the respective bed exactly – there must be no gap between the mattress and the frame where the child could get trapped.

How firm should a baby mattress be?

Very firm. If you press firmly into the centre with your flat hand, the mattress should barely give way and immediately return to its original shape. Soft surfaces increase the risk of the face sinking in and insufficient air circulation.

How long can a baby sleep in a co-sleeper?

The first six months are a guideline. As soon as the child can sit up or pull themselves up independently, the open side to the parents' bed becomes a risk, and it's time to switch to a closed cot.

Can I replace the travel cot mattress with a thicker one?

This is not advisable. A higher mattress reduces the distance to the top edge of the side walls, and a softer one increases the risk of sinking in. Use the mattress specified by the manufacturer for the respective bed.

Does my baby need a duvet in the travel cot?

No. In the first year of life, neither duvets, pillows, nor cot bumpers belong in the bed. Instead, a suitable sleeping bag should be used, which cannot slip over the head or restrict leg movement.

Is a travel cot suitable as a permanent children's bed?

Only to a limited extent. The included insert, at 4 to 6 cm, is significantly thinner than a proper child's mattress, which is 8 to 12 cm high. For occasional nights and holidays, this is not a problem, but it is not recommended for daily use over months.

This article provides general information and is not a substitute for medical advice.