S and Z Sounds

The letter s in European Portuguese is not one sound. It is four — [s], [z], [ʃ], [ʒ] — and the one you produce depends entirely on where the letter sits in the word and what consonant, if any, follows it. Add in the spellings ss, c, ç, and z, and you have what is probably the most important spelling-to-sound system in Portuguese. Get it right and you sound Portuguese. Get it wrong — especially if you substitute Brazilian intervocalic habits — and you sound foreign in every sentence. This page lays out the full system, grounds it in position-based rules, and then works through the edge cases and the common errors.

The four sounds

All four sounds are familiar to English speakers — you produce them every day. The challenge is learning which spelling maps to which sound in which position.

The letter s — four behaviours by position

The letter s alone has four positional allophones. Read this section carefully; it is the backbone of Portuguese sibilant pronunciation.

Position 1: Word-initial or after a consonant → [s]

At the start of a word, or immediately after another consonant within a word, s is [s].

Position 2: Between vowels → [z]

When s stands between two vowels — whether within a word or at the junction between words that are pronounced together — it is [z]. This is the famous "intervocalic s."

Position 3: Syllable-final before a voiceless consonant → [ʃ]

When s closes a syllable — whether inside a word (before another consonant) or at the end of a word — and the next sound is voiceless ([p, t, k, f, s] and their relatives) or the word is followed by a pause, s is [ʃ] ("sh").

Position 4: Syllable-final before a voiced consonant → [ʒ]

When s closes a syllable and the next sound is voiced ([b, d, ɡ, v, z, ʒ, m, n, l, ɾ] and vowels across word boundaries), s becomes voiced too — [ʒ] ("zh," like the s in measure).

A special case: word-final -s before a vowel → [z]

When a word-final s is followed — in connected speech — by a word that begins with a vowel, the s is [z]. This is voicing assimilation across a word boundary, and it is a reliable feature of natural Portuguese.

The letter ss — always [s]

Unlike single s, the digraph ss is always [s]. It never voices, never palatalizes. It appears only between vowels (ss does not occur word-initially or word-finally in Portuguese).

The contrast with single s is meaningful: casa [ˈkazɐ] (house, single s between vowels) versus cassa [ˈkasɐ] (cassa fabric — a lightweight cloth). Double the s, and you defeat the voicing that intervocalic s normally triggers.

The letter c — [k] or [s], depending on the next vowel

The letter c has two pronunciations based on the following vowel:

• Before a, o, u → cor, cuba*.
• Before e, i → cinco, centro*.

The letter ç — always [s], only before a, o, u

The letter ç (c with cedilha) is the solution to a spelling problem: how do you write [s] before a, o, u — positions where plain c would be read as [k]? Answer: you add the cedilha. The ç therefore appears only in positions where c alone would misrepresent the sound.

A spelling rule: ç is never written at the start of a word and never before e or i. If you see ce or ci, the c alone is already [s]; no cedilha is needed. Verbs can alternate between the two spellings across conjugations: começar (infinitive — ç before a) / começo (I begin — ç before o) / comece (subjunctive — c before e, no cedilha needed, same sound).

The letter z — [z] or [ʃ/ʒ] depending on position

The letter z behaves similarly to s, but with its own distribution. In onset positions (word-initial, between vowels) it is [z]. In coda positions (syllable-final, word-final) it behaves exactly like syllable-final s — [ʃ] before voiceless, [ʒ] before voiced, [z] before a vowel across word boundaries.

Spelling alternations in plurals and conjugations

Portuguese spelling sometimes flips between c, ç, z, s across morphological forms to preserve the same underlying sound in new positions. A few common patterns:

• Verb alternation c ↔ qu: ficar (to stay) → fiquei (I stayed, 1sg preterite). The c [k] before a needs to become qu before e to keep the [k] sound.
• Verb alternation ç ↔ c: começar → comece (pres. subj.). The ç before a becomes c before e, both pronounced [s].
• Plurals with -z final: luz → luzes [ˈluzɨʃ]. The final [ʃ] of luz becomes intervocalic and therefore [z] in the plural.
• Plurals with -s final: mês [meʃ] → meses [ˈmezɨʃ]. Same logic — the s is now between vowels, so [z].

The Brazilian contrast — why this matters

One of the sharpest differences between European and Brazilian Portuguese is in the treatment of syllable-final s and z. In most of Brazil, final s is simply [s] — três is [tɾes], mas is [mas], os livros is [os ˈlivɾus]. In Lisbon, final s is [ʃ] or [ʒ] — três is [tɾeʃ], mas is [maʃ], os livros is [uʒ ˈlivɾuʃ]. This is probably the single most audible difference between the two varieties.

Learners who have studied Brazilian Portuguese often carry the [s] pronunciation into European contexts. The result is intelligible, but it immediately marks you as a speaker of the wrong variety. In European Portuguese, commit to the [ʃ] / [ʒ] pronunciation for syllable-final s and z. It is not optional — it is the standard.

Within European Portuguese, intervocalic s is rigidly [z] — casa is [ˈkazɐ], always. Brazilian speakers also use [z] here, so this is not a contrast. The [s] pronunciation of intervocalic s only appears in ss (double s): massa [ˈmasɐ] versus mesa [ˈmezɐ]. Learners sometimes make the mistake of using Brazilian intervocalic pronunciations like [ˈkasa] (instead of [ˈkazɐ]) because they are "spelling-pronouncing" — saying single s as [s]. Resist this; let your ears hear what natives actually say.

The full spelling-to-sound summary

Common Errors

Error 1: Saying intervocalic s as [s] instead of [z]

Spelling-pronouncers — especially those from English or Spanish — often give single s between vowels its voiceless value. Portuguese voices it.

Error 2: Saying final s as [s] instead of [ʃ]

This is the classic Brazilian-to-European transfer error, and also common among learners coming from Spanish or English.

Error 3: Failing to voice syllable-final s/z before a voiced consonant

Learners often say [ʃ] everywhere and miss the [ʒ] before voiced consonants.

Error 4: Not linking final s before a vowel

Portuguese links the final s of one word to the initial vowel of the next as [z]. Beginners often pause or break the link.

Error 5: Confusing s and ss between vowels

Learners who forget that ss blocks voicing will voice it: massa becomes [ˈmazɐ] — which would mean nothing (and would collide with masa, also not a word).

Error 6: Producing ç as [ts] or [θ]

English and German speakers sometimes read ç as [ts] or [θ] (the French value or the Castilian value). In Portuguese, ç is simply [s].

Key Takeaways

• The letter s has four pronunciations: [s] initially or after a consonant; [z] between vowels; [ʃ] syllable-final before voiceless; [ʒ] syllable-final before voiced.
• Final s before a vowel across a word boundary becomes [z] (os amigos [uz ɐˈmiɡuʃ]).
• The digraph ss is always [s] and appears only between vowels.
• The letter c is [k] before a/o/u and [s] before e/i; the letter ç is [s] before a/o/u.
• The letter z is [z] initially or between vowels, but behaves like coda s ([ʃ]/[ʒ]) in syllable-final position.
• Portuguese spelling flips between c and qu, between ç and c, between z and s to keep pronunciation consistent across morphological forms.
• The most audible Brazilian vs. European contrast is in final s/z: Brazil uses [s], Lisbon uses [ʃ]/[ʒ].
• Single s between vowels is always [z] in Portuguese; there is no exception outside ss spellings.
• When in doubt about a plural or a conjugation, trust the voicing rule: intervocalic → voiced, coda → placed and palatalized by context.