How do I check if my baby is too warm in a sleeping bag?

Where do I feel — chest, neck or hands?

Official UK pages agree on the same patch of skin. The Lullaby Trust says feel the chest or the back of the neck. The NHS SIDS page says the same, and adds: do not worry if hands or feet feel cool — that is normal. Tommy’s heatwave advice repeats chest or back of the neck, because hands and feet run cooler than the rest of the body.

Which? (11 June 2026) adds the same rule: do not judge temperature by hands and feet. Flushed cheeks or sweat at the hairline can appear with a hot, sweaty chest — still use the chest or neck as the official check, then change a layer.

What do I change first if the chest feels too warm?

Tog charts assume you can run this check. The method is: feel, then change one thing — a clothing layer or the bag — using that bag’s own guide. The Lullaby Trust will not publish one clothing-and-tog chart for every product.

1. 1
   Feel chest or back of neck Slide a hand inside the neck of the bag onto the chest, or to the back of the neck. Do not use hands or feet as the decision.
2. 2
   If hot or sweaty, remove one clothing layer Lullaby Trust and NHS: remove one or more layers of bedclothes or bedding. Under a bag, that usually means a baby grow off, or a vest only, or — in really hot weather — a nappy, which both Lullaby Trust and Tommy’s list as fine.
3. 3
   Or move to a lower tog on that bag’s table Read the hangtag for the measured room temperature. Do not stack a second bag, and do not put a blanket on top of a bag.
4. 4
   Re-check after a short stretch The same official pages ask you to check regularly, not once at bedtime. If the room has climbed, measure it again at cot height.
5. 5
   Stop here if you think this is a fever A high temperature is not a tog problem. Do not wrap an unwell baby more warmly. Use NHS fever advice or call 111 / your GP.

Are cool hands a reason to put on a higher tog?

No. The Lullaby Trust FAQ is written for this exact worry: hands and feet will usually be cooler, which is normal. Which? explains the circulation point: extremities often feel cooler than an adult’s, so they are not a reliable monitor. Add a tog or a clothing layer only if the chest feels cold, and only after you have measured the sleep room.

If you are using a sleeping bag and the chest is cold, the Lullaby Trust’s move is an extra clothing layer or a higher-tog bag — not a second bag, and not a blanket on top.

What if my baby has a fever or is unwell?

This guide stops at the official overheating check and the clothing or tog change. Fever and illness belong to the NHS. The Lullaby Trust says an unwell baby may feel warmer than usual; dress them for the room and do not wrap them more than usual. It points you to your GP, 111, and the NHS page on a high temperature in children. The Lullaby Trust Baby Check app is their symptom tool — not a tog chart.

If you are worried the baby is significantly unwell, seek medical advice. MayTally does not give clinical advice and does not decide whether a temperature is a fever.

How often should I repeat the check?

The Lullaby Trust’s line is to check regularly, because the 16–20°C range is a guide and every baby is different. Practical moments: at bedtime, after a night feed, if the heating or a window changes, and on hot days when a south-facing room climbs. Pair the skin check with a room thermometer in the sleep room, not a hallway thermostat.

In shortOfficial records name one check: chest or back of the neck. Cool hands are normal. Hot or sweaty skin: take off a layer or drop a tog on the bag’s table. Fever stays on the NHS side of the line.