Does Being Bilingual Cause Speech Delay? No — Here’s the Evidence

By Julia Taylor, B.App.Sc. (Sp.Path.), M.Hlth.Sc., CPSP 6 min read

Let's answer the search query directly: no, learning two languages does not cause speech delay. The American Speech-Language-Hearing Association is unambiguous — bilingual children acquire vocabulary at a rate comparable to monolingual peers when you count words across both their languages (ASHA, n.d.). If a well-meaning relative has told you to 'just pick one language', this article is for them too.

How bilingual toddlers actually store words

A bilingual toddler's vocabulary is distributed across languages: 'milk' in one, 'zapatos' in the other, some things in both. Count only one language and you can badly underestimate what the child knows — which is why proper assessment always considers all the languages a child uses (ASHA, n.d.).

So when you tally your child's words (worth doing monthly), count the combined set: every word in either language, counting cross-language duplicates once. That's the honest measure of their vocabulary.

Should we drop to one language? (No.)

Even when a bilingual child IS a late talker, the professional guidance does not recommend switching to one language (ASHA, n.d.). Language is language: a strong, rich model in any language builds the foundation, and the language you speak most fluently and lovingly is the one where you can offer the best model. Dropping the home language can cost connection with family and culture — with no evidence of a speech benefit in return.

Mixing languages, by the way, is typical bilingual development, not confusion. Toddlers borrow whichever word is handiest, exactly like bilingual adults do.

When to check — same rules, both languages

Bilingualism doesn't cause delay, but bilingual children can still have language delays at the same rate as anyone else — and they deserve the same early attention. The red flags are identical, applied across the combined languages: few words for their age in total, no two-word combinations by two, poor understanding in the stronger language, lost skills, or your own persistent worry (CDC, 2026c; NIDCD, 2022). If any of those apply, ask for an evaluation that looks at both languages — and never accept 'it's just the bilingualism' as a reason to skip one (ASHA, n.d.).

Meanwhile, everything on this site works bilingually: follow the lead, narrate, pause, expand — in whichever language is yours. The word kits and the Talking Journey target concepts ('more', 'go', 'all gone') that every language has its own beautiful words for.

The takeaway

Two languages, one perfectly capable brain. Count words across both languages, keep speaking the language you love best, ignore advice to 'just pick one' — and if you're ever worried, seek an assessment that evaluates both languages, early.

Sources & further reading

American Speech-Language-Hearing Association. (n.d.). Late language emergence (Practice Portal). https://www.asha.org/practice-portal/clinical-topics/late-language-emergence/
Centers for Disease Control and Prevention. (2026c). Milestones by 2 years. https://www.cdc.gov/ncbddd/actearly/milestones/milestones-2yr.html
National Institute on Deafness and Other Communication Disorders. (2022). Speech and language developmental milestones. https://www.nidcd.nih.gov/health/speech-and-language

A friendly note (and the fine print)

This article is general educational information only. It is not speech therapy, therapeutic advice, an assessment, a diagnosis, or a substitute for individualized professional care, and reading it does not create a therapist–client relationship. Every child is different — if you have any concerns about your child’s speech, language, hearing or development, please consult your own certified speech-language pathologist, pediatrician or family health professional, who can advise you about your individual child. See when to talk to a professional for how to find one.

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