The following is a list of when 75% of children have mastered speech sounds. (Photo Articulation Test, 1969, Pendergast et al, and Stoel-Gammon, 1985.)
Limited consonant sound use results in unintelligible speech and often indicates a motor speech disorder (apraxia) or phonological disorder. Check out these norms and the list of “red flags” which indicate that speech therapy is likely needed to help your child learn to be understood.
By 18 months -
Child produces 3 to 6 different consonant sounds with each child having a little different consonant inventory.
By 24 months –
Initial Sounds - /p, b, m, t, n, d, h, k, g/
Final Sounds - /p, m, n/
Produces Most Vowel Sounds Correctly and at least 6-8 different consonant sounds.
By 28 months –
Initial Sounds – /d, f/ and “y”
Final Sounds - /s, d, k, f/ and “ng”
By 32 months –
Initial Sounds - /w/
Final Sounds - /t, b, r/
By 36 months –
Initial Sounds - /s/
Final Sounds - /l, g/ and “er” endings
Child uses at least 9-12 different consonant sounds.
By 40 months –
Initial Sounds - /l, r/
Some consonant blends – bl, br, tr
Final Sounds – /v/ and “sh”
By 44 months –
Initial Sounds – “sh” and “ch” and fl
Final Sounds – “ch”
By 48 months –
Initial – sp, st, kl
After 48 months –
Initial - /z, v/ and “j”and th”
Final - /z/ and “th” and “j”
RED FLAGS for CHILD’S ARTICULATION SKILLS that warrant a referral to a speech-language pathologist for evaluation. (Stoel-Gammon 1994).
Numerous Vowel Errors -
Most children have mastered nearly all vowel sounds by age 2. Some errors are still acceptable are age 2, but by age 3, all vowels be mastered (with exception of /r/ vowels).
Widespread Deletion of Initial Consonants
By 2 a child should use at least 3 to 4 different consonant sounds at the beginnings of words.
By 3 a child should have a large repertoire of initial consonants.
Substitution of Back Consonants /k/ and /g/ or /h/ for a variety of Consonants
This is atypical phonological development and should be targeted even in very young children.
Deletion of Final Consonants after age 3
By 24 months in language delayed children some final consonant deletions are expected, but by 36 months, all children should be producing words with ending consonant sounds.
Again there is variation in individual children, but for the most part, parents should understand close to all of what a child says by age 3, and strangers should understand all of what a child says by age 4, even if errors are still present.
For more information about how to treat speech sound disorders, check out my DVD Teach Me To Talk with Apraxia and Phonological Disorders. Here’s the link -