Where Should My Baby Sleep?

The six-month rule, and why every body agrees on it

There is very little in baby sleep that the UK, Irish, American and Australian health bodies all state the same way. Where the baby sleeps is the exception. The Lullaby Trust: babies "should always be in the same room as you for the first six months for sleep, day and night." The NHS uses almost the same words. The HSE in Ireland says "the safest place for your baby to sleep is in a cot in the same room as you." The American Academy of Pediatrics quantifies it — room-sharing "can decrease the risk of SIDS by as much as 50%" — and Red Nose Australia lists it as one of its six safe sleep recommendations.

Note the two halves of that sentence. Same room, separate sleep space. Room sharing and bed sharing are different things, and the six-month advice refers only to the first. The Lullaby Trust also adds a line worth remembering before you spend money: "There are no devices on the market that can replace having a parent or carer in the same room as baby for safer sleep."

What counts as a sleep space

The test is short. A sleep space is firm, flat, and its own. The Lullaby Trust's checklist for a mattress is three questions: is it firm, so the baby's head sinks in by no more than a few millimetres; is it entirely flat, with no raised or cushioned areas; does it have a waterproof layer. If the answer to all three is yes and it fits the frame with no gaps, you have what you need.

In practice that means a cot, a cot bed, a bedside crib, a Moses basket, a carrycot or a travel cot. The Lullaby Trust's list of what a baby actually needs for safer sleep is short enough to quote in full: a cot or Moses basket, a portable sleep space, a mattress, a sleeping bag or sheets with a lightweight blanket, a room thermometer, and a car seat — the last for travel only.

Bedside cribs and next-to-me cots

A bedside crib is still a separate sleep space, so it satisfies the room-sharing advice while keeping your baby within arm's reach. The Lullaby Trust notes that since 2020 all bedside cribs in the UK should meet BS EN 1130:2019, which means the side should no longer fully drop down.

What is not a sleep space

This is where most of the risk sits, because these things are sold for babies and are often comfortable to look at. The Lullaby Trust advises against soft-sided pods or nests, pillows, duvets or thick heavy bedding, cot bumpers, bouncy chairs, baby hammocks, bean bags, baby swings and sleep positioners. Its reasoning is about the airway: it advises against "letting babies sleep in anything that keeps them in a seated or inclined position as this can restrict their breathing."

The AAP puts the same idea as a rule with a number: "Any surface that inclines more than 10 degrees isn't safe for your baby to sleep on", and it names nursing pillows and lounger-style products as things not to use for sleep. Both bodies say the same thing about accidental naps: if your baby falls asleep in a car seat, pram, swing, carrier or sling, move them onto a firm flat surface on their back as soon as you can.

One point that trips people up. A British Safety Standard is not a safe-sleep certification. As the Lullaby Trust puts it, "there is no safety standard related to sudden infant death syndrome (SIDS). This means that even if a product meets the relevant British Standards, it won't necessarily be safe when it comes to reducing the risk of SIDS." And on the marketing claim you will see most often, that no baby has died of SIDS while using a given product: because SIDS in the UK is now thankfully rare, that claim proves nothing.

When your baby can move to their own room

Not before six months. That is the floor, not the target, and nothing obliges you to move your baby at six months and a day. The guidance simply stops applying with the same force after that point, and the decision becomes yours.

Two things do not change when the room does. Your baby still sleeps on their back until their first birthday, and the cot still stays clear. The NHS is specific: do not use pillows, duvets, cot bumpers, loose blankets, soft toys, or anything to keep your baby in place such as pods or nests. Position matters too — keep the cot away from windows with direct sunlight, radiators and other heat sources, because babies cannot regulate their own temperature.

If your baby was born early

Safer sleep advice follows corrected age. The NHS advises following it for a year from your baby's due date rather than their birth date, which pushes the whole timeline back accordingly.

Travel cots and second sleep spaces

Travel cot mattresses are noticeably thinner than a cot mattress. The Lullaby Trust says that is fine for a main sleep space provided the mattress is firm, flat, in good condition and meets British safety standards, and warns against putting folded blankets or a quilt underneath to make it feel softer. Red Nose Australia takes a more conservative line, describing portable cots as designed for occasional or short-term use rather than a permanent replacement for a standard cot. If you are choosing between them, the UK position is the more permissive one and the Australian the more cautious — both agree the mattress that came with the cot is the only one to use.

When to ask

Speak to your health visitor, public health nurse or GP if you are worried about where your baby is sleeping, if the only place they will settle is somewhere you know is unsafe, or if you cannot afford a safe sleep space. The Lullaby Trust runs a baby safety helpline on 0808 802 6869 and can point you towards baby banks, which supply cots and mattresses free of charge. Nobody should be improvising a sleep surface for want of money.