Accent Mark Rules | Portuguese (Portugal) Grammar

European Portuguese uses four diacritics plus a cedilha. Each one is informative — none are decorative — and together they form a system in which a written word transparently encodes its pronunciation. Once you know the rules, you can look at any Portuguese word and predict (a) which syllable carries the stress, (b) whether the stressed vowel is open or closed, and (c) whether any vowel is nasalised. You can also work the system in reverse: hearing a word, you can predict where its accents will land.

This page is the systematic reference. The accents covered:

Acute (´) — stress + open vowel quality.
Circumflex (^) — stress + closed vowel quality.
Tilde (~) — nasalisation.
Grave (`) — contraction (crase) of a + a only.
Cedilha (¸) — soft ç (/s/ before a, o, u).

The cedilha is not technically a diacritic in the same family as the four accent marks, but it is closely tied to the system and learners benefit from seeing all five marks together. A dedicated page treats it in detail at The Cedilha.

The big picture: why accents exist

Every Portuguese word with more than one syllable has a default stress position determined by its ending. The full statement is at Stress Patterns, but the short version is:

Words ending in -a, -e, -o (with or without a final -s) and verb forms ending in -am, -em, -ens: stress falls on the penultimate syllable by default. casa, mesa, falo, jovens, falaram.
Words ending in any other letter (a consonant, -i, -u, or a nasal -ã / -ão): stress falls on the final syllable by default. falar, papel, comum, irmão, feliz.
Words stressed on the antepenultimate syllable are the third class — never the default.

A written accent appears precisely when stress breaks the default. That is the whole rule, and it is bidirectional: knowing the spelling tells you the stress; knowing the stress tells you whether to write an accent.

The acute and circumflex carry an extra job. On a, e, o, they not only mark stress but also signal vowel quality: acute = open, circumflex = closed. This is unique to Portuguese among the major Romance languages — Spanish accents only mark stress. So when you see avó vs avô, you are reading not just "stress on this syllable" but "stress on this syllable, with this vowel quality."

💡

The system is bidirectional. Once you internalise the default-stress rules, you can take any Portuguese word in writing and predict its pronunciation, including which vowels are open or closed. You can also take any word you have heard and write it with the correct accents. This is the great compensation for the slightly intricate diacritic system: there is no separate spelling memorisation for each word, the way English requires.

The acute accent ( ´ )

The acute marks stress + open vowel quality.

On a, e, o — stress + open vowel

These three vowels have a meaningful open/closed contrast in Portuguese. The acute signals the open version is stressed.

á — open /a/, the bright "ah" of English father. café, lápis, açúcar, árvore.
é — open /ɛ/, the "eh" of English bed. café, médico, é, pé, século.
ó — open /ɔ/, the rounded "aw" of English got (RP) or bought (US). só, avó, herói, próximo, óculos.

O café está pronto na mesa.

The coffee is ready on the table. (café = open é, stressed final)

A árvore mais alta do parque é uma sequoia.

The tallest tree in the park is a sequoia. (árvore = open á, stressed antepenult)

A minha avó faz os melhores bolos.

My grandmother makes the best cakes. (avó = open ó, stressed final)

O meu médico recomendou-me mais exercício.

My doctor recommended I do more exercise. (médico = open é, stressed antepenult)

Está só um pouco cansado, vai descansar.

He's just a little tired, he's going to rest. (só = open ó, monosyllable with mandatory accent)

On i, u — stress only

The high vowels i and u have no open/closed distinction in Portuguese. The acute on í or ú therefore marks only stress, not vowel quality.

í — stress on /i/. público, lápis, país, raízes.
ú — stress on /u/. público, açúcar, baú, saúde.

O público aplaudiu calorosamente o concerto.

The audience warmly applauded the concert. (público = í marks stressed antepenult)

O Brasil é um país enorme.

Brazil is an enormous country. (país = í breaks the diphthong, marking hiatus stress)

A saúde é o mais importante de tudo.

Health is the most important thing of all. (saúde = ú marks stressed hiatus)

A Marta foi ao baú buscar uma manta antiga.

Marta went to the trunk to fetch an old blanket. (baú = ú marks stress on the second of two hiatus vowels)

The hiatus rule is worth flagging: a stressed i or u that immediately follows another vowel (and forms a separate syllable rather than a diphthong) takes an acute. país has two syllables (pa-ís) — the i is stressed and bears the accent. Compare pais (parents), one syllable, no accent — here ai is a diphthong and the stress falls naturally on the a.

The circumflex ( ^ )

The circumflex marks stress + closed vowel quality. Like the acute, it appears only on stressed vowels — but where the acute opens them, the circumflex closes them.

On a, e, o only

â — closed /ɐ/, a centralised mid-low vowel. câmara, lâmpada, ânimo, âmbito.
ê — closed /e/, the "ay" without the off-glide of English day. você, três, mês, português, pêssego.
ô — closed /o/, the pure "oh" of French eau or German o. avô, pôr, pôde, robô.

The circumflex never appears on i or u in modern PT-PT — the open/closed contrast simply doesn't exist for those vowels.

Você fala português há quanto tempo?

How long have you been speaking Portuguese? (você = closed ê; português = closed ê on the final syllable)

Trouxe três pacotes de pêssego em calda.

I brought three packets of peach in syrup. (três, pêssego = closed ê)

O meu avô tem uma câmara muito antiga.

My grandfather has a very old camera. (avô = closed ô; câmara = closed â)

Vou pôr a chave em cima da mesa.

I'll put the key on top of the table. (pôr = closed ô; circumflex distinguishes the verb 'to put' from the preposition por)

Acute vs circumflex — the minimal pairs

The clearest demonstration that accents are not decorative is the set of minimal pairs distinguished only by acute vs circumflex. The stress falls on the same syllable in each pair; only the vowel quality (and therefore the meaning) differs.

Acute (open)	Circumflex (closed)	Distinction
avó /a'vɔ/	avô /a'vo/	grandmother / grandfather
pé /pɛ/	pê /pe/	foot / the letter P
só /sɔ/	são (no relevant pair, but contrast só vs verb sou)	only / I am
pôde /'podɨ/	pode /'pɔdɨ/	he was able (preterite) / he can (present); pôde keeps acute-shaped ô to distinguish — this is one of the AO90 retentions

A avó da Maria faz tricô; o avô joga sueca.

Maria's grandmother knits; the grandfather plays cards. (the pair distinguishes the two grandparents)

Tens algum pé direito? — A do pé é a letra pê?

Do you have some right foot? — Is the one for foot the letter P? (joke contrast: pé = foot, pê = the letter P)

Ontem ele pôde sair, hoje não pode.

Yesterday he was able to go out, today he can't. (pôde = preterite with circumflex; pode = present, no accent — distinguished by accent shape and presence)

The avó / avô pair is the textbook case. Both are paroxytones ending in -o, both have stress on the final syllable (which is otherwise unmarked because the words are monosyllabic in the relevant sense), and the only distinction is open ó vs closed ô. Get the accent wrong and you have called your grandmother a grandfather — a real, meaning-altering error.

💡

If you ever feel uncertain whether a vowel is open or closed in an unfamiliar word, look the word up in Priberam or any modern Portuguese dictionary — the entry will give the IPA and the accent. The contrast is always preserved in writing, so you cannot guess by ear; you have to know.

The tilde ( ~ )

The tilde marks nasalisation of a vowel. It appears only on a and o, giving ã and õ.

Where the tilde appears

ã — nasal /ɐ̃/, the nasalised central /ɐ/. manhã, irmã, lã, romã.
ão — nasal diphthong /ɐ̃w̃/. The most common nasal ending in Portuguese: pão, mão, irmão, coração, opinião, então.
ãe — nasal diphthong /ɐ̃j̃/. Less common but distinctive: mãe, cães, pães, capitães, alemães.
õe — nasal diphthong /õj̃/. The default plural of -ão nouns: limões, opiniões, lições, corações, leões.

A minha mãe fez pão de centeio para o jantar.

My mother made rye bread for dinner. (mãe = ãe nasal diphthong, pão = ão nasal diphthong)

As lições da nova professora são muito interessantes.

The new teacher's lessons are very interesting. (lições = plural -ões; são = -ão default-stressed)

Os meus dois irmãos vivem na Alemanha.

My two brothers live in Germany. (irmãos = plural of irmão)

Comprei dois pães e um pacote de manteiga.

I bought two loaves and a packet of butter. (pães = plural of pão, ãe diphthong)

Os corações dos peixes são minúsculos.

Fish hearts are tiny. (corações = plural of coração)

The plural -ão / -ões / -ães / -ãos pattern

Singular -ão words form their plural in three ways, depending on the word:

Singular	Plural	Pattern	Examples
-ão	-ões	Most common (about 70% of cases)	coração → corações, lição → lições, opinião → opiniões
-ão	-ães	Smaller class, mostly Latin -anus	pão → pães, mão → mãos (irregular!), capitão → capitães, alemão → alemães, cão → cães
-ão	-ãos	Smallest class, often from Latin -anus in different lineage	irmão → irmãos, mão → mãos, cidadão → cidadãos, cristão → cristãos, órfão → órfãos

There is no fully reliable rule for which plural a given -ão word takes — the patterns are historical and must be learned word by word. As a working heuristic: abstract nouns and most common nouns take -ões (coração → corações, opinião → opiniões), while family / nationality words and a few common nouns take -ãos or -ães (irmão → irmãos, alemão → alemães).

Os meus irmãos têm opiniões muito diferentes sobre política.

My brothers have very different opinions about politics. (-ãos and -ões, contrasting plural endings)

Tilde and stress

A subtle point: the tilde marks nasalisation, not stress. In nasal diphthongs (ão, ãe, õe) at word-end, the stress usually falls on the tilde-bearing vowel because the word ends in a nasal vowel and that is the default-stressed position. But in words like órfão (orphan), the stress is on the ó (proparoxytone), and the tilde on ã marks only nasalisation, not stress.

O órfão chegou ao orfanato em janeiro.

The orphan arrived at the orphanage in January. (órfão = stress on the proparoxytone ó, tilde marks nasal ã)

Os órgãos do corpo humano são complexos.

The organs of the human body are complex. (órgãos = same pattern: proparoxytone with nasal final)

These cases — where the acute and the tilde both appear in the same word — are rare but well-defined. The acute marks stress; the tilde marks nasality.

The grave accent ( ` )

In modern PT-PT spelling, the grave accent has only one function: marking the contraction (called crase) of the preposition a + the feminine definite article a / as → à / às. It is not a stress mark and never appears on any other vowel.

Crase with the article

a + a → à (preposition to/at
- feminine article the)
a + as → às (same with plural article)

Vou à praia amanhã.

I'm going to the beach tomorrow. (a + a praia → à praia)

A mãe deu um abraço à filha.

The mother gave her daughter a hug. (a + a filha → à filha)

Saímos de casa às oito da manhã.

We left home at eight in the morning. (a + as oito → às oito)

Telefonei à Ana ontem à noite.

I called Ana last night. (a + a Ana → à Ana; a + a noite → à noite)

Crase with demonstratives

The crase also fuses a with the demonstratives aquele / aquela / aqueles / aquelas / aquilo, producing àquele, àquela, àqueles, àquelas, àquilo. The grave is on the initial a of the demonstrative.

Refiro-me àquele dia em julho.

I'm referring to that day in July. (a + aquele → àquele)

Devolvi o livro àquela professora simpática.

I returned the book to that nice teacher. (a + aquela → àquela)

Não dei muita atenção àquilo que ele disse.

I didn't pay much attention to what he said. (a + aquilo → àquilo)

When is crase used?

Crase appears whenever both conditions are met:

The preposition a would be required (because the verb governs a: ir a, telefonar a, dirigir-se a; or because a is the relevant preposition for the construction).
The following noun phrase begins with the feminine article a / as (or with aquele/aquela/aquilo).

If either condition fails, no crase. If you would say Vou ao Porto (no crase, because the noun is masculine — o + a contracts to ao, not à), then Vou à Lisboa would be the analogous form for a feminine — except Lisboa is a city without an article, so we just say Vou a Lisboa. This is one of the trickier corners of Portuguese punctuation. See Crase Errors for detailed treatment.

💡

The grave accent is not used to mark stress in any Portuguese word. If you see à or às or àquele, you are looking at a contraction, not a stress mark. There are no other uses in modern PT-PT spelling.

The cedilha ( ¸ )

The cedilha is the small hook under c, giving ç. It marks /s/ before a, o, u — the back vowels — where bare c would otherwise be /k/.

coração /koɾɐ'sɐ̃w̃/ — cedilha gives /s/ before a.
moço /'mosu/ — cedilha gives /s/ before o.
açúcar /ɐ'sukɐɾ/ — cedilha gives /s/ before u.

The cedilha is never used before e or i: there, bare c already gives /s/ (cedo, cinco). And the cedilha never starts a Portuguese word — it appears only inside or at the end of a syllable, never word-initially.

A força do coração faz milagres.

The strength of the heart does miracles. (força, coração both with cedilha-/s/)

Já fiz o trabalho — agora vou descansar um pouco.

I've already done the work — now I'm going to rest a bit. (fiz no cedilha; faço would be 1sg present with cedilha)

For the full treatment of the cedilha, including its appearance in verb conjugation, see The Cedilha.

When does an accent appear? — the systematic table

Here is the rule expressed as a complete table. For any accented vowel in PT-PT, you can name which rule produces the accent.

Pattern	Why accented?	Examples
Oxytone ending in -a, -e, -o (with or without -s)	Breaks the paroxytone default — accent marks both stress and vowel quality	café, sofá, jacaré, avó, você, três, português, parabéns
Oxytone ending in -em / -ens	Breaks the paroxytone default for verb-style endings	também, porém, parabéns, armazéns
Paroxytone ending in a consonant or -i, -u, -ã, -ão	Breaks the oxytone default	fácil, útil, ímpar, hífen, júri, órfão
Proparoxytone (any ending)	No default puts stress on the antepenult; always accented	médico, lâmpada, política, rápido, último, câmara, ânimo
Stressed i or u in hiatus (preceded by a different vowel, forming a separate syllable)	Accent breaks the diphthong reading and marks the hiatus	país, saúde, baú, raízes, juízo
Crase: à, às, àquele, àquela, àquilo	Marks contraction of preposition a + article/demonstrative	à praia, às oito, àquele dia

Vamos passar o fim de semana na ilha — vou ao café da Maria pedir indicações.

We're spending the weekend on the island — I'll go to Maria's café to ask for directions. (café = oxytone with acute; ilha, ao = no accent needed)

O médico do hospital de Coimbra é o melhor da região.

The doctor at the Coimbra hospital is the best in the region. (médico = proparoxytone, mandatory accent)

Sentem-se nesta câmara enquanto a Ana fala com o diretor do liceu.

Sit in this chamber while Ana speaks with the head of the school. (câmara = proparoxytone, mandatory accent)

País, saúde, baú e juízo — todas estas palavras têm um i ou u acentuado em hiato.

Country, health, trunk, and judgement — all these words have an accented i or u in hiatus.

Walking through the logic

A few illustrative cases to show the system at work.

falar — ends in -r (consonant), so the default is oxytone. Stress is final, default applies, no accent. Result: fa-LAR.
casa — ends in -a, default paroxytone. Stress on the penult, default applies, no accent. Result: CA-sa.
café — ends in -e, default would be paroxytone, but actual stress is final. Accent required. Acute on é indicates open vowel quality. Result: ca-FÉ with open /ɛ/.
fácil — ends in -l, default would be oxytone, but actual stress is on the penult. Accent required. Acute on á indicates open a. Result: FÁ-cil.
lâmpada — proparoxytone. No default puts stress on the antepenult, so the accent is always required. Circumflex on â indicates closed /ɐ/. Result: LÂM-pa-da.
pão — monosyllable ending in nasal diphthong -ão. Tilde marks nasalisation; stress is automatic since there's only one syllable. No additional accent.
avó — paroxytone ending in -o. The default would be paroxytone stress, which is fine — but the o is open, requiring an acute to distinguish from avô (closed). Both avó and avô are written with an accent; the accent shape carries the vowel quality.
você — oxytone ending in -e. Default would be paroxytone, but actual stress is final. Accent required. Circumflex on ê indicates closed /e/. Result: vo-CÊ.
país — paroxytone in -s, default paroxytone. But the i is in hiatus with the preceding a — they are two syllables, and the i is stressed. Accent required to mark the hiatus and the stress on í. Result: pa-ÍS.

Falo português com a minha avó todas as semanas.

I speak Portuguese with my grandmother every week. (português = closed ê, oxytone; avó = open ó)

O médico do hospital diz que precisas de mais saúde e menos café.

The hospital doctor says you need more health and less coffee. (médico = proparoxytone, saúde = hiatus ú, café = oxytone open é)

AO90: which accents were affected?

The Acordo Ortográfico 1990 (effective in PT from 2009) made several changes to PT-PT diacritics. The most important ones:

1. Trema (¨) abolished

The trema was used in pre-AO90 BR to mark a pronounced u in gu/qu: lingüiça, freqüência, eqüino. PT-PT had already abolished the trema in 1945, so this is a non-change for PT-PT. Modern PT-PT writes linguiça, frequência, equino without any diacritic — readers must learn from context whether the u is silent or pronounced.

Pre-AO90 BR: lingüiça, freqüência (with trema)

The trema marked the pronounced u — abolished by AO90.

AO90: linguiça, frequência (no diacritic)

Modern spelling drops the trema; pronunciation must be learned with the word.

2. Differential accents dropped

A few accents that distinguished homographs were eliminated. The reform's logic: context disambiguates.

Pre-AO90	AO90 (current)	Disambiguated
pára (verb form, 3sg of parar)	para	was distinguished from preposition para
pêlo (hair / fur)	pelo	was distinguished from pelo (per the)
pélo (1sg of pelar)	pelo	was distinguished from preposition contraction
pólo (pole, sport)	polo	was distinguished from polo (per the, archaic)

O autocarro para na próxima paragem.

The bus stops at the next stop. (para = AO90 verb form, no longer distinguished from the preposition)

O cão tem o pelo macio.

The dog has soft fur. (pelo = AO90, no accent; pre-AO90 wrote pêlo)

A handful of differential accents were retained because the alternative would create real ambiguity. The most important is pôde (he was able to — preterite, 3sg of poder), which keeps its circumflex to distinguish it from present pode (he can). Without this accent, pôde and pode would be indistinguishable, and the tense difference matters.

Hoje ele não pode vir, mas ontem pôde.

Today he can't come, but yesterday he was able to. (pode = present, pôde = preterite — the accent matters)

3. Accents on third-person plural verb forms dropped

The 3rd-person plural of ver, ler, crer, dar used to carry circumflex on the doubled vowel:

vêem, lêem, crêem, dêem (pre-AO90)
veem, leem, creem, deem (AO90)

The hiatus is now written without the accent. This affects only this small set of verbs.

Eles veem o filme todas as semanas.

They see the film every week. (AO90 spelling)

As crianças leem em silêncio.

The children read in silence. (AO90 spelling — pre-AO90 was lêem)

Os pais creem nas promessas dos filhos.

Parents believe in their children's promises. (AO90 spelling)

Espero que eles deem uma resposta clara.

I hope they give a clear answer. (AO90 spelling — pre-AO90 was dêem)

4. Acute on certain -eia words (already PT-PT standard)

PT-BR pre-AO90 wrote idéia, assembléia, jibóia, herói, heróico. Most of these had already lost the accent in PT-PT before AO90 (PT-PT writes ideia, assembleia, etc.). So this is a BR-mostly change; PT-PT readers see no difference for these words.

5. PT-PT vs PT-BR variant accents retained

A few words have different accent forms in PT-PT and PT-BR because the pronunciation differs:

António (PT-PT, with acute) vs Antônio (PT-BR, with circumflex) — the same name, different vowel quality.
fenómeno (PT-PT, acute) vs fenômeno (PT-BR, circumflex).
bónus (PT-PT, acute) vs bônus (PT-BR, circumflex).

These are not AO90 changes — they are stable PT-PT vs PT-BR distinctions that AO90 explicitly preserved.

O António é português; o Antônio é brasileiro.

António is Portuguese; Antônio is Brazilian. (same name, different accent reflecting different vowel quality)

O fenómeno é raro mas bem documentado.

The phenomenon is rare but well documented. (PT-PT spelling with acute on the open ó)

Common mistakes

❌ cafe (no accent)

The acute on *café* is mandatory — the word is an oxytone ending in *-e*, so it breaks the paroxytone default. Without the accent, the spelling would predict *CA-fe* (penultimate stress), which is wrong.

✅ café

coffee

❌ avo for grandmother (no accent)

*Avó* (grandmother, open ó) and *avô* (grandfather, closed ô) both require their accents. Without an accent, *avo* would be a non-word; the accent is structural, not optional.

✅ avó (grandmother), avô (grandfather)

Two distinct words, distinguished by the accent shape.

❌ Vou a praia (no grave accent)

*A praia* alone means 'the beach' (article + noun). To mean 'to the beach', the preposition *a* contracts with the article *a* into *à*, with the grave accent. Missing the grave changes what you said.

✅ Vou à praia.

I'm going to the beach.

❌ medico, lampada, politica (no accent on proparoxytones)

Every proparoxytone (antepenult-stressed word) requires an accent. There is no exception. Writing them without an accent is a spelling error.

✅ médico, lâmpada, política

doctor, lamp, politics — all proparoxytones, all accented.

❌ irmao (no tilde)

The tilde on *ã* in *irmão* marks the nasal diphthong *ão*. Without the tilde, the spelling would predict *ir-MA-o*, two syllables, with no nasalisation — completely different word, wrong pronunciation.

✅ irmão

brother

❌ pao, mae, leoes (no tildes)

All three need tildes: *pão* (bread), *mãe* (mother), *leões* (lions). The tilde is not optional decoration — it marks the nasal vowel that defines the word.

✅ pão, mãe, leões

bread, mother, lions

❌ lições (using cedilha before plural -ões)

Trick: *lições* IS correct. Cedilha appears before *ç* before *o* even in plural. Don't drop the cedilha when pluralising *-ção* words.

✅ lição → lições, coração → corações

The cedilha is preserved across the singular-to-plural change because the *c* is still before a back vowel.

❌ pêlo to mean 'fur' in modern writing

Pre-AO90 spelling. Since 2009, *pelo* (no accent) is the standard form, even when meaning 'hair' or 'fur'. Context disambiguates from the preposition contraction *pelo*.

✅ pelo (fur, hair, or contraction of por + o)

The same spelling now serves both meanings; readers disambiguate from context.

❌ vêem, lêem, dêem in modern writing

Pre-AO90 spellings. Since 2009: *veem, leem, deem* without circumflex.

✅ Eles veem o filme. As crianças leem. Espero que deem uma resposta.

AO90 spellings without the circumflex on doubled vowels.

❌ pais (parents) when meaning 'country'

*Pais* (one syllable, no accent) means 'parents'. *País* (two syllables, accent on í) means 'country'. The accent marks the hiatus and changes the word entirely.

✅ os meus pais (my parents) vs. o meu país (my country)

Two completely different words distinguished by a single accent.

Key takeaways

The acute marks stress + open vowel quality on a, e, o; on i, u it marks only stress (no open/closed contrast).
The circumflex marks stress + closed vowel quality on a, e, o only.
The tilde marks nasalisation on a and o (giving ã, õ); essential for nasal vowels and diphthongs.
The grave accent is reserved for the contraction à (and its plural às, plus àquele/àquela/àquilo); it is never a stress marker.
The cedilha signals /s/ for c before a, o, u; never used before e, i; never word-initial.
The default stress rule is the foundation: no accent when stress falls on the default position; accent appears exactly when stress breaks the default.
Proparoxytones always carry an accent — without exception.
Hiatus stress on i / u following another vowel takes an acute (país, saúde, baú).
AO90 changes to PT-PT diacritics: trema abolished (already so since 1945 in PT); some differential accents dropped (pára → para, pêlo → pelo); 3rd-person plural circumflex dropped (vêem → veem, lêem → leem); minimal pair pôde / pode retained.
PT-PT vs PT-BR: variant accents on António / Antônio, fenómeno / fenômeno, bónus / bônus — these are stable variety differences, not AO90 changes.