What Tog Duvet for a Child: A Room-Temperature Guide

The Question Most Guides Skip: Is a Duvet Even Right Yet?

What tog duvet should a child sleep under? For a lot of the age range parents are actually searching this for, the honest answer is that the tog number isn't where the guidance starts. UK safer-sleep advice is built around room temperature and the child's age first, and only reaches a specific duvet once those two things are settled — and for babies, current guidance from the NHS and the Lullaby Trust is that a duvet or quilt isn't the right bedding in the first place.

Sudden infant death syndrome (SIDS) — sometimes still called cot death — is the sudden and unexplained death of an apparently healthy baby up to 12 months old, and the NHS is clear that overheating is one of the known risk factors, alongside things like exposure to cigarette smoke. Its safer-sleep advice sets out specific bedding rules for that reason: keep a baby's cot clear of pillows, duvets, cot bumpers, loose blankets and soft toys, use a firm flat mattress, and dress the baby in lightweight blankets, sheets or a well-fitting sleep bag instead of anything heavier. The risk is highest in the first six months and continues through the first year, and for babies born prematurely the same precautions apply for a year measured from their original due date rather than their birth date.

The Lullaby Trust, the UK charity most closely associated with this guidance, states the same principle from the other direction: babies don't need a hat indoors and shouldn't sleep under a duvet or quilt, specifically to help prevent overheating. That's a narrower rule than most parents expect walking into a nursery aisle, and it's the reason a search for "what tog duvet for a baby" doesn't really have a clean answer — the recommended product for that age group isn't a tog-rated duvet at all.

The 16–20°C range both organisations point to

Where the NHS and the Lullaby Trust agree in detail is room temperature. The NHS recommends keeping a baby's room between 16°C and 20°C, and the Lullaby Trust states the same range, adding that this — combined with light bedding or a lightweight, well-fitting sleep bag — is what it considers a comfortable setup. Both recommend using an actual room thermometer rather than guessing, since a room can read one temperature to an adult standing in it and a noticeably different one at the specific spot a cot sits in, away from radiators, direct sun or draughts.

Why There's No Official Tog Chart for Children

It's worth saying plainly: neither the NHS nor the Lullaby Trust publishes a chart matching room temperature to a specific tog number or clothing layer for children, and the Lullaby Trust addresses this directly on its own site. It notes that families "understandably" often ask for exactly that — a chart or more specific guide matching room temperature to clothing, layers and tog — and explains it isn't able to provide one, because bedding products vary too much between manufacturers for a single fixed table to hold true across the market.

That matters for how to read the tog numbers printed on children's duvets and sleep bags. Tog is a bedding-industry measure of warmth, set by the manufacturer on that specific product — it isn't a figure issued by a safety authority against a fixed room-temperature table. The two systems sit alongside each other rather than plugging into one another: the safer-sleep guidance tells a family what temperature range to hold a room at and how to dress a baby for it in general terms, while the tog number on an individual duvet or sleep bag is the manufacturer's own statement of how warm that particular product runs. There's no single official conversion between the two, which is exactly what the Lullaby Trust is telling families when it declines to publish one.

Checking the Child, Not Just the Thermometer

Both organisations put the same practical check ahead of any label reading. To tell if a baby is too hot or too cold, feel their chest or the back of their neck rather than their hands or feet — cool hands and feet are normal and don't, on their own, mean a baby needs another layer. If the skin at the chest or neck feels hot or sweaty, the guidance from both the NHS and the Lullaby Trust is the same: remove one or more layers of bedding or clothing rather than leaving it and hoping the room cools down on its own.

This check matters regardless of what bedding is in use, because a thermometer reading and a child's actual temperature can diverge — a room can sit correctly within the 16–20°C range and a specific baby can still be running warm under too many layers, or the reverse. The room-sharing recommendation sits in the same practical category: both organisations recommend a baby sleep in the same room as a parent or carer, day and night, for at least the first six months, partly because it makes exactly this kind of hands-on check easier to do consistently through the night rather than relying on a monitor alone.

Once a Duvet Is Part of the Room

None of this means tog becomes irrelevant once a child is old enough for a duvet to be the right product for their room — it means the same room-temperature logic that governs a baby's sleep bag carries forward into how that duvet gets chosen. A warmer bedroom calls for a lower tog rating; a colder one calls for a higher one, and the honest way to know which is which is the same room thermometer already recommended for the safer-sleep period, not a guess based on the calendar or the season a duvet happened to be bought in. Checking the child by touch — the same chest-or-neck method — remains the more reliable signal than the number on the label, whatever that number says.

In practice, UK retailers that stock children's or junior bedding, including John Lewis and Dunelm, list tog rating alongside age or size filters, which makes it possible to shop for both at once rather than treating them as separate decisions. That's useful once a family has already worked out, from the room and from the child, that a duvet is the right product — it isn't a substitute for that first step.

The Takeaway

Age and room temperature decide the starting point, not the tog rating. For babies, the NHS and the Lullaby Trust both point to the same 16–20°C range, monitored with a thermometer, and to lightweight bedding or a sleep bag rather than a duvet, specifically to manage the overheating risk linked to SIDS. There is no official chart that turns a room-temperature reading into a specific tog number for a child's bedding — the Lullaby Trust says so directly — so once a duvet genuinely is the right product for a child's age and room, the sensible approach is the same one behind the safer-sleep advice itself: check the room with a thermometer, check the child by touch, and treat the tog number on the label as one input rather than the whole answer.

References

• Room temperature — The Lullaby Trust
• Sudden infant death syndrome (SIDS) — NHS