Speech Sound Development

August 26, 2019 1 Comment

What Is Speech?

Speech is the way we pronounce words. The term ‘speech’ is used to describe the individual sounds that are used in words as we talk.

Speech sound development looks at both the acquisition of individual speech sounds (articulation development) and the way in which these sounds are organised into speech patterns (phonological development).

Please see below the ages in which your child should typically be able to produce each sound:

Speech Sound Development
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What are Phonological Processes?

Children’s speech often does not sound like adult speech because they make typical, systematic ‘sound replacements’. These ‘sound replacements’ are called phonological processes.

Phonological processes are patterns of sound errors that typically developing children use to simplify speech as they are learning to talk. There are many different patterns of simplifications or phonological processes.

Phonological Processes
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Speech Intelligibility

Your child’s speech should typically become easier to understand as they get older. Here’s a guide to follow:

  • By 2 years of age children can be understood by familiar adults most of the time
  • By 3 years of age children can be understood by unfamiliar adults most of the time
  • By 4 years of age children can be understood by unfamiliar adults almost all of the time
  • By 5 years of age children can be understood by unfamiliar adults all of the time

If by 4 years, less than half of what your child says is understood by strangers, you should arrange for your child to be seen by a Speech & Language Therapist for an assessment.


  • Bowen, C. (1998). Developmental phonological disorders. A practical guide for families and teachers. Melbourne: ACER Press.
  • Flipsen, P., Jr (2006). Measuring the speech intelligibility of conversational speech in children. Clinical Linguistics and Phonetics, (20) 4, 303-312.

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  • […] concerned about your child’s speech sound development check out our Speech Sound Development page to find out about the ages and stages of typical speech sound […]

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