WHAT THE AGREEMENT SAYS

One language,
almost one spelling.

Written Portuguese was spelled two ways for most of the 20th century.

Portugal kept silent letters such as the c in acção; Brazil had long dropped them. The spelling agreement signed in Lisbon on 16 December 1990 set out a shared spelling, and kept two forms only where pronunciation really differs.

≈ 98% of the vocabulary unified

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Drop letters nobody says
Keep two spellings where speech differs
Fewer hyphens, one alphabet
Spelling follows pronunciation

THE SHORT ANSWER

Write what you
say, mostly.

The agreement changes spelling only.
Portugal's government says pronunciation and word use stay the same.

SILENT LETTERS

Acção became ação

A c or p that no educated pronunciation sounds is dropped: ação, diretor, ótimo. Letters that are said, as in pacto or ficção, stay.

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TWO SPELLINGS

Facto and fato are both fine

Where speakers really differ, both forms are correct: facto in Portugal, fato in Brazil; sector or setor.

See the numbers

HYPHENS

Autoestrada, one word

Many prefixes now join directly: autoestrada, extraescolar. Before r or s the letter doubles: antirreligioso, minissaia.

The rules in brief

A QUICK WORD CHECK

Did this word
change?

Pick a word to see what the 1990 agreement does to it. The bar shows how much the spelling moved for a reader used to the old Portuguese (European) norm.

Word check

Choose a wordpactofacto / fatoacçãoauto-estradamicro-onda

pactoUnchanged

The c is pronounced in every educated pronunciation, so it stays. The same goes for compacto, ficção and apto.

facto / fatoBoth correct

The c is said in Portugal but not in Brazil, so the agreement allows both. Other pairs include sector/setor and receção/recepção.

acçãoNow ação

The c was silent in every educated pronunciation, so it goes: ação. Likewise direção, coleção, adoção and ótimo.

auto-estradaNow autoestrada

A prefix ending in a vowel joins a word starting with a different vowel: autoestrada, extraescolar, plurianual.

micro-ondaKeeps its hyphen

When the prefix ends in the same vowel the next word begins with, the hyphen stays: micro-onda, anti-ibérico, contra-almirante.

Source: text of the Acordo Ortográfico da Língua Portuguesa (1990), as promulgated in Brazil by Decree 6,583 of 29 September 2008.

Examples are taken from the text of the agreement itself (Bases IV, XVI and the section on the trema).

TWO NUMBERS WORTH KNOWING

A big agreement,
a small change.

The figures come from the agreement's own explanatory note,
based on a corpus of about 110,000 words.

≈ 98%

Share of the general vocabulary spelled the same

The explanatory note says the new text is strong enough to unify the spelling of about 98% of the general vocabulary. Earlier attempts in 1945 and 1986 aimed for close to 100% and failed.

UNIFIED · EXPLANATORY NOTE

0.54%

Words that lost a silent c or p

Just over 600 words in about 110,000, the note says. Few, but they include very common ones such as acção, actor, director and óptimo.

SILENT LETTERS · EXPLANATORY NOTE

The note adds that about 0.5% of the vocabulary (just over 575 words) keeps two accepted spellings, and that double accentuation such as António/Antônio covers about 1.27% (around 1,400 words).

FOUR RULES IN BRIEF

What to change
when you write.

Most words are untouched. These are the changes the agreement itself highlights, with its own examples.

Drop the silent c and p
Ação, ativo, diretor, batizar, Egito. Keep letters you actually pronounce.
Lose the trema
The two dots over u are gone from Portuguese words: cinquenta, frequentar, linguística. They survive only in words from foreign names, such as mülleriano.
Join prefixes, double r and s
Autoestrada, coeducação, antissemita, contrarregra. Keep the hyphen before the same vowel or h: micro-onda, anti-higiénico.
Lower-case the months
Days, months and seasons start with a small letter: segunda-feira, outubro, primavera.

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THE ALPHABET

Twenty-six letters,
officially.

Base I of the agreement lists the alphabet for the first time and adds k, w and y, making 26 letters. The note gives the reasons: dictionaries already listed words starting with them, learners need to know their place in the order, and many words in the African Portuguese-speaking countries use them.

Their use stays restricted: names from other languages and their derivatives (Kant, kantismo; Darwin, darwinismo), foreign place names (Kuwait, Malawi) and international symbols and units such as K for potassium.

Questions

Questions people ask

When did the new spelling start?

The agreement was signed in Lisbon on 16 December 1990. Portugal's government says it has been in force there since 13 May 2009, with a six-year transition. Brazil applied it from 1 January 2009, with a transition that ran to 31 December 2015.

Does the agreement change how Portuguese is pronounced?

No. Portugal's Council of Ministers resolution 8/2011 says it concerns spelling only, and that pronunciation and the use of words stay unchanged.

Is Portuguese now spelled exactly the same everywhere?

Almost. The explanatory note says about 98% of the general vocabulary is unified. Where educated pronunciations differ, two spellings are accepted, such as facto and fato, or António and Antônio.

Which countries signed it?

Angola, Brazil, Cape Verde, Guinea-Bissau, Mozambique, Portugal and São Tomé and Príncipe signed in 1990, with observers from Galicia taking part in the preparatory work.

Is there a free tool to convert a text?

Yes. Portugal adopted the Vocabulário Ortográfico do Português and the Lince converter as official tools, both free on the Portal da Língua Portuguesa, built by the linguistics institute ILTEC.

One language,
almost one spelling.