Sound Safari
Speech Sound Guide
The Voiced TH Sound: Norms, Challenges & Word Lists
The /th/ sound is one of the later sounds children master — typically by age 8. This guide covers when /th/ develops, what typically goes wrong, simple ways to practice it, and over 90 /th/ words organized by position.
When should a child say /th/?
Developmental norms — when the /th/ sound typically emerges and is mastered.
Source: McLeod & Crowe (2018), AJSLP.
A child still substituting or distorting /th/ after age 8 is a good candidate for a speech-language evaluation — earlier if they're hard to understand or frustrated.
Find out where /th/ stands — in 5 minutes
Sound Safari's 23-sound screener checks against the McLeod & Crowe norms above.
Common challenges with /th/
What typically goes wrong — and whether it's age-appropriate.
Stopping
/th/ → /d/
Typically resolves on its own by around age 4; worth a check-in if it persists.
What helps →
Show the tongue position in a mirror — /d/ is hidden behind the teeth, voiced /th/ pokes between them. Practice slowly with the tongue visible.
How to practice the /th/ sound
Practical starting points for parents and SLPs. Always follow your SLP's plan if your child is in therapy.
- 1 Tongue between the teeth. Voiced /th/ is made with the tongue gently between the top and bottom teeth — same position as voiceless /th/ — but with the voice on, producing a buzz.
- 2 Buzz, don't blow. Voiced /th/ uses the voice. Touch the throat — it should buzz. If only air is coming out, that's voiceless /th/ (think); if it buzzes, that's voiced /th/ (this).
- 3 Mirror practice. Use a mirror so the child can see the tongue between the teeth. The position is the same as voiceless /th/ — the only difference is the voice.
- 4 Contrast pairs — /th/ vs /d/. Voiced /th/ is often replaced with /d/ ("dis" for "this"). Use pairs like they/day, then/den, those/doze to train the tongue-between-teeth position.
- 5 Start with frequent words. Voiced /th/ shows up in many everyday words: this, that, them, the, they, mother, father, brother. Practice with these first.
/th/ word lists by position over 90 words
Every word from the Sound Safari practice library. The /th/ in each word is bolded.
Initial — /th/ at the start of the word (30)
Medial — /th/ in the middle of the word (30)
Final — /th/ at the end of the word (30)
IEP goals for /th/
A starting point for SLPs writing articulation goals — across the six therapy levels.
Goal progression — tap a level to see the goal
Sample goal — word level
"Given a verbal model, [student] will produce /th/ in the initial position of words with 80% accuracy across 3 consecutive sessions."
Track /th/ progress automatically
Sound Safari logs every trial against your goals and writes the SOAP note for you.
/th/ sound — frequently asked questions
At what age should my child say the voiced /th/ sound? +
Most children produce voiced /th/ correctly by age 8. About half can do it by age 6. Voiced and voiceless /th/ are among the latest English sounds to develop.
Is it normal for my child to say "d" for voiced /th/? +
Yes — substituting /d/ ("dis" for "this", "dem" for "them") is developmentally typical up to about age 7. If it persists past age 8, it's worth a check-in.
What's the difference between voiced and voiceless /th/? +
Both use the same tongue-between-teeth position. Voiceless /th/ (think, thumb, math) is silent — just air. Voiced /th/ (this, that, mother) buzzes — the voice is on.
How can I help my child practice voiced /th/ at home? +
Show the tongue position in a mirror, touch the throat to feel the buzz, and use contrast pairs (they/day, those/doze). Practice with everyday words like "this", "that", "mother".
When should we see a speech therapist about voiced /th/? +
If voiced /th/ is still being replaced with /d/ past age 8, see an SLP. (Note: voiced /th/ is one of the latest sounds and many adults keep some "d-ish" quality casually.)
Can older children and adults still correct voiced /th/? +
Yes — /th/ is treatable at any age. The tongue position is visible, and once voiceless /th/ is in place, adding voicing is straightforward.
Related sounds
Sounds that pair, contrast, or are commonly confused with /th/.
