How common is Selective Mutism in children?

When a child speaks freely at home yet falls silent at school, it isn't shyness or defiance — it's a recognised anxiety-based difficulty, and you are far from alone.

In short

Selective Mutism is uncommon but not rare — most estimates place it at roughly 1 in 140 children (under 1%), with some studies in school settings reporting figures a little higher. It is seen slightly more often in girls, and it tends to become noticeable when a child starts nursery or school, where the expectation to speak in new settings first appears. It is an anxiety-based difficulty — these children genuinely want to speak but feel unable to in certain situations — and with the right understanding and support, the outlook is very encouraging.

Understanding the numbers

• Prevalence: widely cited as about 0.7–0.8% of children — close to 1 in 140 — though numbers vary because the condition is often under-recognised and quietly mistaken for ordinary shyness.
• When it shows: it most commonly emerges between ages 3 and 6, when a child meets settings outside the family. A diagnosis is usually considered only once the difficulty has lasted more than a month and isn't simply the normal settling-in period of a new school.
• The pattern that matters: a child speaks comfortably and often a great deal at home, yet is consistently unable to speak in specific situations such as the classroom — despite having the language ability to do so.
• It rarely travels alone: it frequently sits alongside social anxiety, and supporting that underlying anxiety is central to helping a child find their voice.

Because it is genuinely uncommon, many families spend a long time wondering what is happening — knowing it is a real, named, treatable condition is often the first relief.

When to seek a check

Seek a friendly developmental check if your child consistently does not speak in certain settings (school, with relatives, in shops) for more than a month, while speaking freely elsewhere — especially once the first few weeks of a new setting have passed. Early, gentle support tends to bring the best results, so there is no need to wait and see for long.

The Pinnacle way

AbilityScore® is part of Pinnacle’s developmental assessment. Diagnosis, where needed, requires an appropriately qualified healthcare professional — never from an app or online form. Our clinicians look gently at the whole picture — communication, anxiety and the situations that trigger silence — through a clinician-administered structured assessment, then shape calm, confidence-building speech and language therapy around your child. Begin by exploring what support looks like.

Trusted sources

WHO ICD-11 classification of Selective Mutism within anxiety and fear-related disorders; American Speech-Language-Hearing Association guidance on selective mutism and childhood communication; American Academy of Pediatrics (HealthyChildren.org) guidance on childhood anxiety.

Next step — Wondering if what you're seeing is Selective Mutism? Book a gentle assessment with a Pinnacle clinician.

This is general information, not a diagnosis — individual assessment and diagnosis require an appropriately qualified healthcare professional.