Phonological Processes — Ages of Suppression Cheatsheet
Printable reference of the 12 most common English phonological processes with Bowen (2015) ages of suppression, definitions, and clinical examples.
Overview
Phonological process analysis lives or dies on whether the clinician can tell an age-expected simplification from a persistent disorder. The Bowen (2015) age-of-suppression table is the reference most commonly cited in US graduate programmes and in school-based eligibility reports because it covers every process a clinician will see in connected speech and lists the age by which a typically developing child should no longer be using it. This cheatsheet puts all twelve processes on a single printable page so SLPs can scan a sample transcript, flag each process present, and mark it as age-expected or persistent without flipping through the Bowen textbook.
This cheatsheet is a static reference intended for clinical and educational use. Every page is rendered from a peer-reviewed source and cited below the printable sheet. Clinicians must adapt to the individual patient and to the current edition of any cited instrument manual before clinical use.
How to use this sheet
During a single-word probe or a 100-utterance phonological sample, mark each child production against the target word. When you spot a pattern (e.g., "tup" for "cup", "wabbit" for "rabbit"), find the matching process on this sheet and check the suppression-age column. If the child's age is at or below the listed age, the pattern is age-expected and not a treatment target; if the age exceeds the Bowen band, the process is persistent and belongs on the IEP goal sheet. The cheatsheet pairs naturally with the phonological-process identifier tool — use the tool for quick in-session triage and the cheatsheet as the paper audit trail that goes into the evaluation report. For a bilingual child, cross-reference the suppression ages against the child's second-language phonology before flagging a process as disordered.
“Half the over-referrals I see in kindergarten phonology screenings are cluster reductions on a five-year-old. Cluster reduction suppresses at age 4;0 for /s/+stop clusters but not until 5;0-6;0 for three-element clusters — print the band, stop over-referring.”
Automate this workflow
Stop hand-copying the phonological processes numbers into every report
Upload the session audio and ConductSpeech extracts the metrics, formats them against the published norm band, and drops a ready-to-paste present levels paragraph next to the cheatsheet values. Built for school-based SLPs on 50-student caseloads.
Printable sheet
| Process | Definition | Suppressed by | Example |
|---|---|---|---|
| Cluster reduction | Omission of one consonant in a cluster | 4;0 (two-element) / 6;0 (three-element) | "poon" for "spoon" |
| Final consonant deletion | Omission of a final consonant | 3;3 | "ca" for "cat" |
| Fronting (velar) | Replacing velar /k, g, ŋ/ with alveolar /t, d, n/ | 3;6 | "tup" for "cup" |
| Fronting (palatal) | Replacing palatal /ʃ, tʃ, dʒ/ with alveolar | 4;0 | "soo" for "shoe" |
| Stopping | Replacing fricatives/affricates with stops | 3;0 (/f, s/) / 5;0 (/v, ð, z/) | "tun" for "sun" |
| Gliding (of liquids) | Replacing /r, l/ with /w, j/ | 5;0 (/l/) / 6;0-7;0 (/r/) | "wabbit" for "rabbit" |
| Vocalisation | Replacing syllabic /l, r/ with a vowel | 6;0 | "appo" for "apple" |
| Weak syllable deletion | Omitting an unstressed syllable | 4;0 | "nana" for "banana" |
| Deaffrication | Replacing affricate /tʃ, dʒ/ with fricative | 4;0 | "ship" for "chip" |
| Denasalisation | Replacing nasals /m, n, ŋ/ with oral stops | 2;6 | "dose" for "nose" |
| Prevocalic voicing | Voicing a voiceless consonant before a vowel | 3;0 | "gup" for "cup" |
| Final devoicing | Devoicing a final voiced consonant | 3;0 | "pik" for "pig" |
Ages of suppression from Bowen (2015); percentages are age at which 85% of typically developing children no longer use the process in single words.
Common pitfalls
- Flagging "wabbit" as persistent gliding in a four-year-old. Liquid gliding of /r/ is age-expected all the way to 6;0-7;0.
- Counting age-expected stopping of /v, ð, z/ as a treatment target before age 5;0. These later-developing voiced fricatives have a later suppression age than /f, s/.
- Confusing fronting (a phonological process) with an articulation substitution of /t/ for /k/ in a single word. Fronting is a systematic pattern; a one-off substitution is not.
- Using Bowen suppression ages for a bilingual child without checking the L1 phonology. Spanish L1 children may show "final consonant deletion" that is actually expected in their L1 phonotactics.
Free tools paired with this cheatsheet
Phonological Process Identifier
Free interactive phonological process identifier for speech-language pathologists. Enter a target word and the child production and the calculator flags every matching process from the twelve most common English patterns (cluster reduction, fronting, stopping, gliding, vocalisation, weak syllable deletion, final consonant deletion, deaffrication, denasalisation, prevocalic voicing, devoicing, initial consonant deletion), each tagged with its Bowen (2015) age of suppression so you can see whether the production is age-expected or persistent. Mobile-friendly, client-side, no sign-up.
Open toolPCC Calculator
Free interactive Percent Consonants Correct (PCC) calculator for speech-language pathologists. Enter the consonants attempted and produced correctly from a 50- to 100-utterance connected-speech sample and get the PCC percent plus the Shriberg & Kwiatkowski (1982) severity band (mild, mild-moderate, moderate-severe, severe). Built for SLP intake, IEP eligibility, treatment-progress tracking, and graduate phonological-assessment training. Mobile-friendly, client-side, no sign-up.
Open toolSpeech Sound Development Chart
Free interactive speech sound development chart for speech-language pathologists. Look up the age of acquisition for the 24 English consonants based on the McLeod & Crowe (2018) cross-linguistic systematic review. Filter by age band and word position (initial, medial, final), enter a child age and instantly see which sounds are age-expected versus still developing. Mobile-friendly, client-side, no sign-up.
Open toolRelated cheatsheets
English Consonant Mastery Ages — Printable Chart
Printable McLeod & Crowe (2018) English consonant mastery chart with age of customary production for all 24 consonants, sorted by place and manner.
PhonologySpeech Intelligibility by Age — Printable Reference
Printable reference of unfamiliar-listener speech intelligibility expectations by age, pooled from Coplan & Gleason (1988), Flipsen (2006), and Hustad et al. (2021).
Language samplingMLU-Morpheme Norms by Age — Printable Reference
Printable one-page reference of Mean Length of Utterance in morphemes (MLU-M) expectations by chronological age, including Brown, Miller, and Rice norms.
References
- Bowen, C. (2015). Children's Speech Sound Disorders (2nd ed.). Wiley-Blackwell.
- Dodd, B., Holm, A., Hua, Z., & Crosbie, S. (2003). Phonological development: A normative study of British English–speaking children. Clinical Linguistics & Phonetics, 17(8), 617–643.
- Stoel-Gammon, C. (1985). Phonetic inventories, 15–24 months: A longitudinal study. Journal of Speech and Hearing Research, 28(4), 505–512.
- Shriberg, L. D., & Kwiatkowski, J. (1982). Phonological disorders III: A procedure for assessing severity of involvement. Journal of Speech and Hearing Disorders, 47(3), 256–270.