What is a fever (high temperature) in children?

As a general rule, a temperature of 38C (100.4F) or above is classified as a fever in children.

But this can vary from child to child. Some children may be ill with a lower temperature, while others may have a higher temperature and be perfectly well.

What’s most important is what’s normal for your child. You know your child better than anyone – if you’re concerned about their temperature, they probably have a fever.

Find out how to take your child’s temperature.

When to get medical advice

Mild fevers are usually nothing to worry about, and can often be treated at home. They normally pass in a few days.

Read about how to treat a high temperature in children.

Contact your GP, health visitor or NHS 111 if:

  • your child is under three months old and has a temperature of 38C (101F) or above
  • your child is between three and six months old and has a temperature of 39C (102F) or above
  • the fever lasts more than five days
  • your child has a fit (seizure) for the first time
  • your child also has signs of a serious illness, such as blotchy skin or fast breathing
  • you’re worried about your child – trust your instincts if you think they could be seriously ill