The short answer: two questions and a timeline
Refer when the answer to either of these is yes. First: could a visiting adult who does not know this child follow a normal conversation with them? If a substitute, a parent volunteer, or the office staff regularly cannot, that is enough on its own, at any grade. Second: is the student still making sound errors that most children their age have outgrown? Add a third trigger that has nothing to do with sounds: if the student avoids speaking, gets frustrated by their own speech, or is being teased about it, refer regardless of how mild the errors seem to you.
As a rough guide on intelligibility, most children are understood by an unfamiliar adult most of the time by around age three, and nearly all of the time by around age four or five. Ranges vary by source and by child, so treat these as a signal to look more closely, not a verdict. Only an evaluation by a licensed speech-language pathologist (SLP) can determine whether a child has a disorder. You are never diagnosing. You are flagging.
The timeline matters as much as the criteria. Give yourself two to three weeks to separate a real pattern from first-week nerves, a new-school adjustment, or a cold. Collect dated examples in that window, then refer. Waiting a full quarter to be sure costs the student a quarter of possible service. Our teacher resources and the speech sound development chart are worth having open while you decide.
If an adult who does not know the child cannot follow them in conversation, refer now. Do not wait to see whether it improves.
Signs by grade band
What counts as a concern depends heavily on age, because sounds arrive on a schedule. Early sounds like p, b, m, n, h, w, d, t, k, and g are usually in place by about three or four. Later sounds like l, s, z, sh, ch, j, and v tend to settle by about five or six. The r sound and th sound are typically last, often around six or seven, and th can run to seven or eight. Again, sources differ and children differ.
Use the grade bands below as your quick filter. Anything in the list is worth a conversation with the SLP, even if you are not sure it rises to a referral.
- Preschool and pre-K: family and staff often cannot understand the child, few or no consonants at the ends of words, very short utterances compared with peers, or clear frustration when not understood.
- Kindergarten: unfamiliar adults struggle to follow the child, whole categories of sounds are still substituted (for example every k and g sounds like t and d), or the child cannot hear rhymes and beginning sounds while classmates can.
- First and second grade: errors on s, z, sh, ch, j, l, or v are still present and consistent, sound errors are showing up in spelling, or the child reads aloud far less clearly than they read silently.
- Third grade and up: a persistent r or s distortion the student is now self-conscious about, or any new decline in how clearly a previously clear student speaks.
- Any grade, refer promptly: a sudden change in speech, a voice that is hoarse or breathy for more than about two weeks with no cold, repeating sounds or getting stuck on words with visible struggle, or speech that gets noticeably worse when the student is tired.
- Any grade, refer regardless of severity: the student avoids speaking, says they hate how they talk, or is being teased.
What to document before you refer
A referral with five dated examples gets a faster, better evaluation than one that says the student is hard to understand. The SLP is working out whether this is a pattern, a single sound, a language issue, or something situational, and your examples are the only classroom data they will get.
Spend two weeks jotting on a sticky note. You are not assessing anything. You are showing that a pattern exists across days and settings.
- Dated verbatim examples. Write what the child actually said and what they meant: said tar for star, 9/8; said wed for red, 9/10.
- Who could and could not understand. Note the substitute, the volunteer, a peer, you. Unfamiliar listeners are the meaningful test.
- Situations. One-to-one versus whole group, reading aloud versus casual talk, calm versus excited or tired.
- What helps. Slowing down, facing you, repeating, having seen the words first, or nothing you have tried.
- Other facts. Ear infections, hearing screening result, languages spoken at home, and whether the family has raised the same concern.
Five dated examples of what the student said and what they meant is the most useful thing you can hand the SLP.
How to word the referral
Most districts have a form, and most forms have a box that teachers fill with something vague. Write it like a short case note instead. State the concern, give examples, describe impact, say what you have already tried, and ask a question. Keep it to a paragraph.
Here is a template you can adapt. I am referring [student] for a speech screening. Since the start of the year I have noticed [the pattern in plain words, for example that ending sounds are frequently left off]. Dated examples: [three or four]. Our substitute on [date] and a parent volunteer on [date] both needed the student to repeat several times. The student participates less in whole-group discussion than in partner work, and told me on [date] that they do not like reading out loud. Extra response time and sending passages home in advance help somewhat. Could you observe or screen the student, and tell me what to reinforce in the meantime?
Two things to avoid. Do not label the problem: say the student leaves off ending sounds, not the student has a phonological disorder. And do not soften it into nothing. Phrases like maybe it is just his age give the SLP nothing to act on and can push a needed screening down the pile. If you are unsure whether what you are seeing is speech or language, our explainer on speech versus language disorders sorts the two out in about two minutes.
Check district policy before you talk to the family
Districts differ on whether a teacher contacts the family first, whether a general education intervention period comes before a formal evaluation, and who obtains consent. Ask your case manager, SLP, or administrator how your building handles it before you pick up the phone, because getting the order wrong can delay the very evaluation you are trying to start.
A few process facts are worth knowing. Schools have a duty to identify students who may need special education services, often called Child Find. Parents can request an evaluation in writing at any time. If a student qualifies, services come with measurable goals in an Individualized Education Program (IEP) reviewed at least annually, while a 504 plan provides accommodations rather than services. Timelines and criteria vary by state and district, and legal questions belong with your administrator.
When you do speak with the family, describe behavior and impact, not diagnosis, and say clearly that a screening is a look, not a label. Our post on talking to parents about a speech concern has wording for that conversation, including what to do when a family disagrees.
When it is probably not a referral yet
Not every difference needs an evaluation, and over-referring has a cost: it slows the queue for students who need it more. A few situations usually warrant watching rather than referring, as long as you set a date to check again.
A kindergartner or first grader whose only error is r or th, with everything else clear, is usually within the expected range. A student new to English whose errors match sounds their first language does not use may be showing a language difference rather than a disorder. A child who is quiet in September but talks freely by October was adjusting, and a change during a cold or after dental work is usually just that.
In every one of those cases, write the date you will re-check on your calendar, six weeks out. Watching is only a decision if it has an end date. If English is the question, see our guide on English language learner or speech sound disorder, and for background on what an evaluation might find, our overview of articulation disorder is written in plain language.
Bringing it together
Referring is a low-cost act with a high ceiling. A screening that comes back fine costs an SLP an hour. One that does not can change how a child participates for the rest of elementary school. When you are torn, spend two weeks collecting dated examples, then send the referral with them attached.
While you wait for the screening, keep the student talking. Give extra response time, model correct productions instead of correcting, and keep whole-class sound and listening routines in your day so nobody is singled out. Our activity library and word lists by sound are useful for those five-minute routines and for reinforcing whatever target the SLP names later. They support therapy, they do not stand in for it.