The baby’s age and condition matter alongside a thermometer reading. This guide presents NHS thresholds and emergency signs without giving medication doses.
The short answer
Age and the child’s condition matter alongside the temperature. Use a digital thermometer and record how the measurement was taken.
What to do in everyday care
Offer fluids, continue breastfeeding and check the child regularly. Note the temperature, timing, feeding, urine and changes in behaviour to share with the clinician.
Age and individual context
NHS urgent thresholds include under 3 months at 38°C or higher, and 3–6 months at 39°C or higher. Seek urgent advice also if fever is suspected in these ages.
A common misunderstanding
A lower number does not cancel concerning symptoms. Do not alternate paracetamol and ibuprofen unless a health professional instructs you to; suitability depends on age and circumstances.
When to get help
Difficulty breathing, being hard to wake, a non-fading rash or a first seizure require emergency help. Fever lasting 5 days or dehydration needs urgent assessment. Use local services; NHS numbers are UK-specific.
A moment to think through
Original reflection: prepare a short handover for an urgent call. Which observations describe the child now, rather than only the highest temperature?
Original Launfi reflection · not a clinical caseUnder three months: 38°C needs urgent assessment
For a baby under three months with 38°C / 100.4°F or higher, seek urgent medical assessment. Do not wait several days or assume teething explains it.
A fever at this age needs urgent assessment.
Three to six months: 39°C needs urgent assessment
NHS advises urgent help for a baby aged three to six months with 39°C / 102.2°F or higher. Seek help sooner when concerned about the baby’s condition.
This age-specific threshold needs urgent help.
Act on emergency signs without waiting for a higher number
Difficulty breathing together with being hard to wake requires local emergency services immediately. Do not delay for a different thermometer reading or a completed exercise.
Emergency signs take priority over the number.
Read it. Try it. Come back to why.
Read one point at a time, then use the linked scenario to check your understanding. The practice is a chance to return to the explanation and reflect, rather than a measure of parenting ability.
Practise all 3 questions →