Puberty in boys: changes, age and behaviour

Written by: the Essense teamPublished: Medical review: pending. This article will be reviewed by a doctor before publication.

A father and son cooking and laughing together

Many parents wonder when puberty starts in boys and whether their child's behaviour is "normal". There is no single right age and no single right pace.

When does puberty start in boys?

According to the NHS, puberty can start at any point between about 8 and 14[1]. WHO defines adolescence, as a stage of life, as ages 10 to 19[2].

What changes in the body?

Behaviour: what to expect

Puberty doesn't only change the body. Many children become quieter, more sensitive or more irritable. WHO stresses that supportive environments in the family and at school are important for adolescent mental health[3].

When to talk to a paediatrician

The NHS advises a non-urgent appointment with a doctor if signs of puberty appear before 8 or haven't appeared by 15. It notes that usually there is nothing to worry about[4].

Read also: What is puberty? · Puberty in girls · For parents

Sources

  1. NHS. Puberty (last reviewed 2 April 2026) (2026). www.nhs.uk/conditions/puberty/ (opens in a new tab)
  2. World Health Organization. Adolescent health (health topic). www.who.int/health-topics/adolescent-health (opens in a new tab)
  3. World Health Organization. Mental health of adolescents (fact sheet, 1 September 2025) (2025). www.who.int/news-room/fact-sheets/detail/adolescent-mental-health (opens in a new tab)
  4. NHS. Early or delayed puberty (last reviewed 2 April 2026) (2026). www.nhs.uk/conditions/early-or-delayed-puberty/ (opens in a new tab)