Last updated 2026-07-09
TL;DR
Tongue tie can make certain speech sounds harder to produce, particularly /r/, /l/, /s/, /z/, /th/, and /d/. Most children with tongue tie still develop speech within the typical range, and when a child has a broader speech delay, something else is usually behind it. A speech-language pathologist, not a surgeon, should be the first stop for evaluating speech concerns. The case for lip tie affecting speech is even weaker.
What tongue tie actually is
Tongue tie, or ankyloglossia, happens when the lingual frenulum (the band of tissue under the tongue that connects it to the floor of the mouth) is shorter, thicker, or tighter than usual. That limits how far the tongue can lift, stick out, or move side to side.
How common is it? Estimates are all over the place. A 2020 systematic review in Pediatrics put the range at 0.1% to 10.7% of infants, with a pooled estimate around 3.9% [1]. That spread tells you clinicians still don't agree on what counts as a real tie versus a normal variation in anatomy. Some providers flag nearly any visible frenulum as a tie; others only diagnose it when it's actually limiting function. It also shows up roughly twice as often in boys as girls, though nobody has fully explained why [1].
There's no single agreed-upon diagnostic tool either. The Hazelbaker Assessment Tool for Lingual Frenulum Function and the Kotlow classification are both in use, but neither has become the universal standard, which is part of why research on treatment outcomes is so hard to compare across studies.
So can tongue tie cause speech delay?
It depends on what you mean by "speech delay." Tongue tie can limit the tongue's range of motion enough to make certain sounds physically harder to form, which is an articulation issue, not a language delay. A child with a small vocabulary, who isn't combining words on schedule, or who doesn't seem to understand what's said to them is showing signs of language delay, and tongue tie almost certainly isn't behind that.
The American Speech-Language-Hearing Association notes that ankyloglossia "may" affect articulation, particularly sounds where the tongue tip needs to lift or extend, but adds that many children with tongue tie develop speech normally with no intervention at all [2]. That "may" is doing real work: the link isn't automatic.
A 2017 systematic review in the International Journal of Pediatric Otorhinolaryngology looked at the evidence tying ankyloglossia to speech outcomes and found the existing studies were low quality, making it "difficult to draw firm conclusions" about whether frenotomy actually improves speech [3]. That's still roughly where the science sits.
Where tongue tie is most likely to show up is in a narrow band of sounds: /r/, /l/, /s/, /z/, /th/, /t/, /d/, and /n/, all of which require the tongue tip to reach the alveolar ridge or palate. A child with a tight frenulum might compensate with jaw movement or a different tongue position, which can distort those sounds. But broader delays, like few words, late first words, or not combining words, are much more often linked to hearing loss, limited language exposure, developmental language disorder, autism, or childhood apraxia of speech. If your child is behind on vocabulary or word combinations, tongue tie is unlikely to explain it.
Which sounds are actually at risk
Not every sound carries the same risk. The ones that need the tongue tip to lift, extend past the lower teeth, or touch the roof of the mouth precisely are the vulnerable ones.
| Sound | Why it's affected | Typical age of mastery |
|---|---|---|
| /t/, /d/, /n/ | Need tongue tip at alveolar ridge | By age 3 |
| /l/ | Tongue tip lifts to alveolar ridge | By age 5-6 |
| /s/, /z/ | Groove in tongue tip required | By age 7-8 |
| /r/ | Complex tongue body/tip positioning | By age 6-8 |
| /th/ | Tongue extends past or touches teeth | By age 7-8 |
Sounds like /p/, /b/, /m/, /f/, /v/, /k/, /g/, and most vowels need little or no tongue tip movement, so tongue tie rarely touches them.
Worth remembering: most of the sounds above aren't expected until age 5 to 8, so a 2-year-old who can't say /r/ yet is right on track no matter what their frenulum looks like. Kids also compensate well, and plenty of children with a restricted frenulum land on an alternate tongue placement that sounds perfectly fine. These sound errors have other causes too, including motor planning differences, hearing problems, or just ordinary developmental immaturity. If you're concerned about specific sound errors, the right first step is a speech therapy evaluation, not a surgical consult.
What about lip tie?
Lip tie gets far less research attention than tongue tie, and most of what exists concerns breastfeeding rather than speech. A lip tie happens when the labial frenulum (the tissue connecting the upper lip to the gum) is short or thick enough to limit how the lip curls back or moves. In newborns that can cause a poor latch. For speech, there's very little controlled evidence that it causes delay or meaningful articulation problems.
Sounds that depend on upper lip movement, like /p/, /b/, /m/, /f/, and /v/, could theoretically be affected by a severely restricted lip. In practice the lip has plenty of natural mobility and the frenulum attaches near the midline, so a genuine functional restriction is rare. Most pediatric dentists and speech-language pathologists will tell you lip tie is far more likely to affect dental spacing or breastfeeding than speech. Notably, the American Academy of Pediatric Dentistry doesn't currently list speech delay as a primary reason to release a lip tie [4], and if the evidence were strong, it would likely be in their guidelines by now.
If you've come across claims online that lip tie is behind your toddler's speech delay, take that with a grain of salt. A speech-language pathology evaluation to pin down the actual pattern of delay is a better next step than pursuing a procedure.
Does cutting the tie (frenotomy) actually help speech?
This is where parents most want a clean answer, and the science just isn't there yet. Frenotomy (cutting the frenulum) and frenuloplasty (a more involved surgical revision) are both used. For newborns, the evidence that frenotomy helps breastfeeding is reasonably solid, which is why it's recommended more readily in that context [5].
For speech, it's a different story. The 2017 systematic review mentioned earlier found no high-quality randomized controlled trials on frenotomy for speech outcomes [3], and later reviews land in the same place: the evidence is too thin to say frenotomy improves speech, and the available studies are small, unblinded, and inconsistent [5]. The American Academy of Pediatrics said as much in a 2020 clinical report: "There is insufficient evidence to suggest that frenotomy improves speech outcomes in children with ankyloglossia" [5], which is about as authoritative a statement as exists on this right now.
That doesn't mean frenotomy never helps with speech, just that nobody's run the studies needed to prove it does. Some speech-language pathologists report children producing sounds after a release that they couldn't manage before, especially when it's paired with follow-up myofunctional therapy. But anecdotes aren't evidence, and there's a real risk of seeing what you expect to see.
What most pediatric SLPs and ENTs recommend in practice is trying speech therapy first. If a child has a genuinely restricted frenulum and isn't making progress on specific sounds despite targeted therapy, a surgical consult makes sense at that point. Jumping to surgery before giving therapy a chance is hard to justify given what the evidence currently shows.
A speech-language pathologist can tell you whether tongue tie is actually behind a child's speech trouble, and it comes down to a hands-on oral mechanism exam rather than a glance at the mouth. First they check range of motion: can the child lift the tongue tip to the ridge behind the top teeth with the mouth open, stick the tongue past the lower lip, or sweep it side to side to each corner? Restricted movement here, combined with specific sound errors, points toward a real functional problem rather than anatomy that just looks unusual. One classic sign is the "heart-shaped tongue," where the tip notches or dips in the middle when a child with a tight frenulum tries to lift or extend it, though plenty of children with a tie never show this clearly. An SLP also watches for compensatory patterns, like leaning heavily on jaw movement instead of the tongue tip, which suggests the child is working around a restriction. And they look at which sounds are affected: errors isolated to /t/, /d/, /n/, /l/, /s/, and /z/, the sounds that need tongue tip elevation, are a lot more telling than scattered articulation mistakes across the board. Appearance alone can mislead in both directions. A frenulum that looks short might not restrict anything if the tongue is strong and mobile, while one that looks fairly normal can still cause trouble if it attaches in an odd spot. Function is what matters. If your child has already gone through early intervention and is still stuck with specific articulation errors past the age those sounds should be mastered, it's reasonable to bring in both an SLP and an ENT. Tongue tie gets blamed for speech delays more often than it deserves, partly because it's visible and has a surgical fix that feels concrete. That convenience can distract from the actual cause. Hearing loss is the contributor most often missed: a child who can't hear clearly can't learn to produce sounds accurately or build vocabulary on schedule. Newborn hearing screening is standard, but mild or progressive hearing loss can show up later, so any child with speech concerns should have a current hearing evaluation[6]. Developmental language disorder, once called specific language impairment, affects roughly 7 to 10% of children and has nothing to do with oral anatomy at all[7]: hearing is normal, structure is normal, but processing language is genuinely hard. Childhood apraxia of speech, a motor planning disorder where the brain struggles to coordinate the movements speech requires, gets mistaken for tongue tie often, since both involve effortful attempts at specific sounds; there's more on that in this piece on childhood apraxia of speech. Autism spectrum conditions also bring speech and language differences, from late talking to communication patterns far more complex than any structural issue could produce, and autism spectrum speech therapy approaches these differently than standard articulation work. Thin language input at home, bilingual mixing, and chronic ear infections cause far more delayed or unusual speech than tongue tie ever does. If you suspect tongue tie is behind your child's speech issues, start with a licensed speech-language pathologist, not a surgeon. An SLP can tell you whether the sound errors match what you'd expect from a restricted frenulum, or whether something else entirely is going on, and can examine tongue mobility directly. If the pattern fits, the usual next step is a trial of speech therapy focused on tongue tip strength and elevation. Plenty of kids improve enough that surgery never comes up; if progress stalls despite steady effort, a referral to an ENT or pediatric surgeon makes sense. For children under 3, early intervention through the IDEA Part C program is free in every state, and you don't need to already know the cause of a delay to get referred[8]. If a toddler has broader delays, like very few words, no word combinations, or not responding to their name, push for a full developmental evaluation instead of zeroing in on tongue anatomy alone. ASHA offers a free tool called "When to Refer" with age-based milestones for exactly this kind of decision[2]. Some families also add structured home practice between sessions: Little Words is an AI-based speech companion built for neurodivergent kids and late talkers, with daily guided activities meant to sit alongside professional therapy rather than replace it. The start quiz can tell you whether it fits your child. One thing worth avoiding entirely: booking a frenectomy off a quick look in a dentist's chair, with no SLP involved, no therapy trial attempted, and no documented speech concern in the first place. That's happening more, and the evidence doesn't back it. For breastfeeding, tongue tie should be addressed as early as possible when it's causing problems, since that feeding window is short. Speech is a different timeline. Most of the sounds tongue tie affects aren't expected to be solid until ages 5 to 8, so releasing a 2-year-old's frenulum to prevent hypothetical future speech trouble isn't supported by evidence. You don't know yet whether a problem will even show up, and therapy is usually the right first move if it does. A frenotomy consultation starts to make more sense once a child is 4 or 5, has done six months or more of speech therapy, is motivated, has a confirmed restriction in range of motion, and still can't produce sounds needing tongue tip elevation. When frenotomy does happen for speech reasons at this age, myofunctional therapy afterward is typically recommended, because cutting the frenulum doesn't automatically undo the compensatory habits and muscle patterns a child has built up, something providers who present surgery as a standalone fix sometimes leave out. Some older children and adults pursue this too, and the same logic applies: speech therapy for adults covers how frenotomy and therapy work together to address leftover articulation patterns after a release. Tongue tie severity is usually graded using the Kotlow classification, based on how much free tongue, meaning the portion that moves freely, remains[9]:| Kotlow Class | Free tongue length | Clinical significance |
|---|---|---|
| Class I (mild) | 12-16 mm | Usually no functional impact |
| Class II (moderate) | 8-11 mm | May affect breastfeeding, less often speech |
| Class III (severe) | 3-7 mm | More likely to restrict function |
| Class IV (complete) | <3 mm | Significant restriction, most likely to need intervention |
What does speech therapy for tongue tie actually look like?
If an SLP decides that tongue tie is restricting specific sounds, therapy usually centers on a few things.
Oral motor exercises to improve tongue tip strength and range of motion. These might include tongue tip taps on the alveolar ridge, lateral tongue movements, and exercises that train the tongue to move independently of the jaw.
Sound-specific practice once enough tongue mobility is there. The SLP targets the affected sounds in isolation, then syllables, then words, then conversational speech in a hierarchy that adjusts based on how the child responds.
Compensatory strategy adjustment. If the child has developed unusual tongue placements to work around the restriction, the SLP helps them unlearn those habits and replace them with more typical placements.
Parent training. For young children especially, what happens between sessions matters as much as what happens in the clinic. SLPs will usually give home practice activities, often 5 to 15 minutes a day, to reinforce what's being worked on.
Myofunctional therapy is a specialized branch of this that focuses on how oral muscle function, resting posture, swallowing, and speech relate to each other. If you're going through a frenotomy, post-op myofunctional therapy is almost always recommended by the operating provider.
For a broader look at how speech therapy speech therapist evaluations and treatment work, that page covers the full process. If in-person therapy is hard to access, online speech therapy has shown comparable outcomes for many articulation goals in research conducted during and after the pandemic.
Here's my most common tongue tie question, answered straight: no, it almost never explains a 2-year-old who has few words or isn't combining words yet. Tongue tie can get in the way of specific sounds that need the tongue tip to lift, but those sounds aren't expected until age 5 to 8 anyway. If your 2-year-old is significantly behind on vocabulary, look at hearing or a language disorder first, and get an SLP evaluation before anything else. Lip tie gets blamed for speech delay too, but the evidence just isn't there. It's more reliably connected to breastfeeding struggles and dental spacing. The sounds that depend on lip movement, /p/, /b/, /m/, /f/, /v/, come in early and don't need much lip mobility to produce correctly. The American Academy of Pediatric Dentistry doesn't even list speech delay as a reason to release a lip tie. See a speech-language pathologist before considering any procedure. Cutting a tongue tie doesn't automatically fix speech, either. The AAP said back in 2020 that there isn't enough evidence to say frenotomy improves speech outcomes. Some kids do better after release paired with myofunctional therapy, but the studies behind that are small and uncontrolled. The standard approach for a child with speech concerns is to try speech therapy first. Surgery on its own, without follow-up therapy, rarely changes speech patterns in any lasting way. If you're wondering which sounds tongue tie could realistically affect, it's /r/, /l/, /s/, /z/, /th/, /t/, /d/, and /n/, all of which require the tongue tip to lift or hit precise spots on the roof of the mouth or teeth. Sounds like /p/, /b/, /m/, /k/, /g/, and most vowels barely use the tongue tip and are rarely an issue. Since several of these sounds aren't mastered until 7 or 8, an error in a younger child is often just typical development, not a tongue problem. So how do you tell the difference? A licensed SLP can look at both the speech pattern and the mouth's structure. Tongue tie usually shows up as trouble with a specific cluster of tip-elevation sounds while everything else stays intact. Broad delays in vocabulary, grammar, or understanding language are almost never caused by tongue tie: hearing loss, developmental language disorder, apraxia, and autism are far more likely explanations and should be ruled out first. There's no cutoff age after which treatment stops being an option. Frenotomy and myofunctional therapy happen in older children, teens, and even adults dealing with speech or other issues tied to tongue restriction. Older patients often need more therapy afterward simply because compensatory speech habits have had longer to set in. Whether it's worth pursuing comes down to how much functional restriction is actually present, which an SLP is best positioned to judge. Posterior tongue tie is more controversial. It describes a frenulum hidden under the tissue that you can't see without feeling for it, and providers disagree on how often it's real versus over-diagnosed. There's barely any research tying it to speech outcomes specifically. If someone tells you your child needs a posterior tie released for speech reasons, it's reasonable to get a second opinion from an SLP who specializes in feeding and oral function first. When you suspect tongue tie, start with a speech-language pathologist rather than a dentist or ENT. An SLP (CCC-SLP) can check whether your child's specific errors actually match what tongue restriction would cause, do an oral exam, and tell you whether a surgical referral makes sense. Going straight to a dentist or surgeon risks getting a structural fix for what might be a motor, language, or neurological issue. The SLP can loop in an ENT or pediatric surgeon later if needed. Tongue tie doesn't always need treatment. Plenty of people have a short or tight frenulum and no problems at all. Treatment only makes sense when there's documented functional difficulty, whether that's with breastfeeding, speech, teeth, or swallowing. Just seeing a frenulum isn't a reason to act on it. The AAP is clear that these decisions should rest on function, not anatomy, and for many kids, watching closely while doing speech therapy is the right call. Tongue tie can contribute to a lisp, especially an interdental lisp, where /s/ and /z/ come out with the tongue pushed between or against the teeth, or a lateral lisp, where air escapes out the sides. Both happen because the tongue tip can't form the precise groove sibilants need. Most lisps in young kids, though, are just a normal part of development and clear up on their own. A lateral lisp is the exception: it's less likely to resolve without help and usually benefits from speech therapy no matter what the tongue anatomy looks like. Myofunctional therapy targets the muscles of the mouth, tongue, and face: how they rest, how they work during swallowing, and how they support speech. It's usually brought in after a frenotomy to retrain habits that built up around the old restriction. Not every child with tongue tie needs it. It matters most after a release in an older child, or when there are real, documented issues with tongue posture or swallowing alongside the speech concerns. Tongue tie does seem to run in families. Research shows familial clustering, and it shows up about twice as often in boys as girls. Some studies point to genes involved in midline development, though the full picture isn't settled. Having a parent or sibling with tongue tie raises the odds a child will have one too, but that doesn't mean it will actually cause problems. It can affect eating, too, not just speech. Past the newborn breastfeeding stage, older kids with tongue tie sometimes struggle to move food around in the mouth, especially chewing tougher textures or shifting food side to side, and some avoid certain textures altogether. An SLP with feeding training or an occupational therapist usually handles this. If your child has both speech concerns and real mealtime struggles, it's worth asking for a combined feeding and speech evaluation.Sources
- Pediatrics (AAP journal), systematic review on ankyloglossia prevalence: Pooled prevalence of ankyloglossia estimated at approximately 3.9% in infants, ranging from 0.1% to 10.7% across studies; roughly twice as common in males
- American Speech-Language-Hearing Association (ASHA), Ankyloglossia clinical topic page: ASHA notes ankyloglossia may affect articulation of sounds requiring tongue tip elevation but that many children develop speech normally without intervention
- International Journal of Pediatric Otorhinolaryngology, systematic review on ankyloglossia and speech: Systematic review found low methodological quality in existing studies and stated it was difficult to draw firm conclusions about whether frenotomy improves speech outcomes
- American Academy of Pediatric Dentistry (AAPD), oral health policies and recommendations: AAPD clinical guidance does not list speech delay as a primary indication for lip tie release
- American Academy of Pediatrics (AAP), Clinical Report on Ankyloglossia and Breastfeeding, 2020: AAP clinical report states there is insufficient evidence to suggest frenotomy improves speech outcomes in children with ankyloglossia
- Centers for Disease Control and Prevention (CDC), Hearing Loss in Children: CDC documents that hearing loss is a leading cause of speech and language delay in children and supports universal newborn hearing screening
- ASHA, Developmental Language Disorder (DLD) overview: Developmental language disorder affects approximately 7% to 10% of children and occurs without structural oral differences
- U.S. Department of Education, IDEA Part C Early Intervention Program: IDEA Part C guarantees early intervention services for eligible children under age 3 in every state at no cost to families
- ASHA, Speech Sound Disorders articulation milestones: ASHA documents age-based mastery ranges for speech sounds including /r/, /l/, /s/ expected by ages 6 to 8; Kotlow classification grades free tongue length
- National Institutes of Health, National Library of Medicine (PMC), Hazelbaker Assessment Tool for Lingual Frenulum Function: Hazelbaker tool assesses both appearance and function of the lingual frenulum including tongue lateralization, elevation, and cupping to determine clinical significance