Developmental Language Disorder (DLD): Signs, Prevalence, and Help
Developmental language disorder (DLD) is a persistent difficulty learning and using language — understanding and putting words and sentences together — with no known medical cause. ASHA cites 7.58–8.5% of 4- to 6-year-olds in UK and Chinese studies. It often overlaps with speech sound disorders, ADHD, and dyslexia.
What DLD is
ASHA describes a spoken language disorder as a persistent difficulty acquiring and using listening and speaking skills across phonology, morphology, syntax, semantics, and pragmatics. “Developmental language disorder” is used when it is a primary disability without a known medical cause that persists at school age and beyond — including when it co-occurs with conditions such as ADHD where the causal link is unclear. Some researchers still use the older term “specific language impairment.”1
NIDCD notes DLD delays the mastery of language skills, that some children with it may not begin to talk until their third or fourth year, and that researchers have linked a genetic variant to inherited language impairment.2
How common it is, and what it travels with
| Measure | Figure |
|---|---|
| DLD, ages 4–6 (UK and China) | 7.58%–8.5% |
| Specific language impairment, US kindergarten | 7.4% |
| Any spoken language disorder, ages 4–5 (several countries) | 6.6%–20.6% |
| DLD among 4-year-olds with speech sound disorder (Australia) | 40.8% |
| ADHD co-occurring with DLD (US) | 22.35% |
| Children with DLD who also have dyslexia | 54% |
DLD figures cited in ASHA’s Practice Portal.1
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Check your child’s speech and language milestones — in 2 minutes.
Causes and what is not a cause
ASHA says researchers do not fully understand the cause of DLD; it is best seen as an interaction of multiple complex factors. DLD tends to run in families, and multiple genetic factors contribute. ASHA is clear that multilingualism is not a cause of speech or language disorders.1
In medical coding, language disorders use ICD-10-CM F80.1 (expressive language disorder) or F80.2 (mixed receptive-expressive language disorder).3
Getting help
- Ask for a speech-language evaluation that includes language, not just speech sounds.
- Mention family history of language or reading difficulties.
- Ask the school to watch reading and writing, given the overlap with dyslexia.
A certified speech-language pathologist can assess language; ASHA’s ProFind lists them.4
About SpeechStep
SpeechStep practices speech sounds for ages 4–8; it does not assess or treat language disorders such as DLD.
Frequently asked questions
What is developmental language disorder?＋
ASHA explains that DLD is the term used when a spoken language disorder is a primary disability without a known medical cause and persists at school age and beyond. NIDCD describes it as a language disorder that delays the mastery of language skills; some children with DLD may not begin to talk until their third or fourth year.
How common is DLD?＋
Common. ASHA cites DLD prevalence of 7.58% to 8.5% among 4- to 6-year-olds in UK and Chinese studies, and a widely cited US estimate of 7.4% for specific language impairment in kindergarten.
Is DLD the same as a speech sound disorder?＋
No — DLD affects language (understanding and forming words and sentences), while a speech sound disorder affects producing sounds. They often co-occur: ASHA cites a 40.8% DLD comorbidity among Australian 4-year-olds with speech sound disorder.
Is DLD linked to dyslexia?＋
Often. ASHA cites a study in which 54% of children with DLD also had dyslexia and 71% of children with dyslexia had DLD, though rates vary across studies.
Put this into practice today
Try the free speech milestone checker, or start daily AI speech practice — every child takes one SpeechStep at a time.
References
4 sources from authoritative bodies. Last reviewed October 2026.
- 1.ASHASpoken Language Disorders — Practice Portal page.
- 2.NIDCDSpeech and Language Developmental Milestones — Fact sheet.
- 3.ASHA2027 ICD-10-CM Diagnosis Codes Related to Speech, Language, and Swallowing Disorders — Coding resource (PDF), 2026.
- 4.ASHAASHA ProFind: Find a Certified Speech-Language Pathologist — Referral directory.