Numbers in Portuguese come in two flavours that both act as determiners. Cardinals (um, dois, três, quatro) count things; ordinals (primeiro, segundo, terceiro) place them in order. Both sit before the noun and — crucially — several of them agree in gender. Beyond the paradigms, this page flags a single fact that catches out every learner sooner or later: European Portuguese bilião means one trillion (10¹²), while Brazilian bilhão means one billion (10⁹). A three-order-of-magnitude difference. Get that wrong in a financial context and you are embarrassing yourself.
Cardinal numbers
Cardinal numbers as determiners sit before the noun and tell you how many.
Tenho dois irmãos e três irmãs.
I have two brothers and three sisters.
Comprei cinco maçãs no mercado.
I bought five apples at the market.
O concerto dura duas horas.
The concert lasts two hours.
Most cardinals are invariable — they do not change form regardless of the noun's gender. The exceptions, which you must memorise, are um/uma, dois/duas, and the hundreds (duzentos/duzentas, trezentos/trezentas, and so on).
Cardinals that agree in gender
| Number | Masculine | Feminine |
|---|---|---|
| 1 | um | uma |
| 2 | dois | duas |
| 200 | duzentos | duzentas |
| 300 | trezentos | trezentas |
| 400 | quatrocentos | quatrocentas |
| 500 | quinhentos | quinhentas |
| 600 | seiscentos | seiscentas |
| 700 | setecentos | setecentas |
| 800 | oitocentos | oitocentas |
| 900 | novecentos | novecentas |
Comprei duas camisas e dois casacos.
I bought two shirts and two coats.
Há duzentas pessoas na sala.
There are two hundred people in the room.
O livro tem trezentas e cinquenta páginas.
The book has three hundred and fifty pages.
Quinhentas mulheres assinaram a petição.
Five hundred women signed the petition.
O projeto custou quatrocentos mil euros.
The project cost four hundred thousand euros.
All other cardinals (três, quatro, cinco, seis, dez, vinte, trinta, cem, mil) are invariable.
Três amigas e três amigos.
Three friends (fem.) and three friends (masc.).
Cinco alunas e cinco alunos passaram no exame.
Five female and five male students passed the exam.
Cem euros chegam para o jantar.
One hundred euros is enough for dinner.
Mil pessoas vieram à manifestação.
A thousand people came to the demonstration.
Cardinals — key forms
| # | Portuguese | # | Portuguese |
|---|---|---|---|
| 1 | um / uma | 16 | dezasseis |
| 2 | dois / duas | 17 | dezassete |
| 3 | três | 19 | dezanove |
| 10 | dez | 20 | vinte |
| 11 | onze | 50 | cinquenta |
| 12 | doze | 100 | cem / cento |
| 13 | treze | 1 000 | mil |
| 14 | catorze | 10⁶ | um milhão |
| 15 | quinze | 10⁹ | mil milhões |
Note the PT-PT forms dezasseis, dezassete, dezanove — Brazilian Portuguese spells them dezesseis, dezessete, dezenove.
Cem vs. cento
Cem is the round hundred. Cento is used in compound numbers from 101 upward.
Tenho cem euros.
I have one hundred euros.
Tenho cento e vinte euros.
I have one hundred and twenty euros.
Há cem alunos na escola.
There are one hundred students in the school.
Há cento e cinquenta alunos na escola.
There are one hundred and fifty students in the school.
Never *cem e vinte — always cento e vinte.
The "e" in compound numerals
Portuguese inserts e between all orders of magnitude in a compound numeral. This is a consistent PT-PT pattern.
cento e vinte
120
duzentos e trinta e cinco
235
mil e quinhentos
1500
dois mil e vinte e quatro
2024
trezentos e noventa e nove
399
setecentos e dezoito
718
The rule of thumb: every "gap" between components takes e. Mil quinhentos without e is not wrong, but mil e quinhentos is the more careful form. Between hundreds and tens/ones, e is obligatory: cento e um, not *cento um.
Milhão, bilião — and the PT-PT vs. BR pitfall
This is the most important note on this page. European Portuguese and Brazilian Portuguese disagree about the meaning of bilião / bilhão — and the difference is three orders of magnitude.
| Number | European Portuguese | Brazilian Portuguese |
|---|---|---|
| 10⁶ | um milhão | um milhão |
| 10⁹ (English: one billion) | mil milhões | um bilhão |
| 10¹² (English: one trillion) | um bilião | um trilhão |
| 10¹⁵ | mil biliões | um quatrilhão |
European Portuguese follows the long scale (échelle longue) historically used in most of Europe. Brazilian Portuguese follows the short scale used in the United States. The consequence is stark:
- Um bilião de euros in PT-PT = one trillion euros (10¹²)
- Um bilhão de euros in BR = one billion euros (10⁹)
- These are 1000 times apart.
O orçamento do estado é de 100 mil milhões de euros.
The state budget is 100 billion euros (10¹¹). (PT-PT — would be 'cem bilhões' in Brazilian)
A dívida pública ultrapassou um bilião de euros.
Public debt exceeded one trillion euros (10¹²). (PT-PT — would be 'um trilhão' in Brazilian)
A empresa vale dois mil milhões de dólares.
The company is worth two billion dollars (2 × 10⁹). (PT-PT)
A NASA gastou mil milhões de dólares nesse programa.
NASA spent one billion dollars on that programme. (PT-PT)
If you work in finance, journalism, science, or any context where large numbers matter, this is one of the most consequential PT-PT/BR differences you will ever learn. Double-check every time.
Milhão, bilião and agreement
Milhão and bilião are nouns (masculine), not determiners strictly speaking. They take de + noun:
um milhão de euros
one million euros
dois milhões de pessoas
two million people
mil milhões de estrelas
one billion stars (PT-PT)
um bilião de células
one trillion cells (PT-PT)
Note the plural milhões and biliões when counted with 2 or more.
Ordinal numbers
Ordinals tell you the order of something in a sequence — first, second, third. Unlike cardinals, all ordinals agree in gender and number.
Paradigm
| # | Masculine | Feminine |
|---|---|---|
| 1st | primeiro | primeira |
| 2nd | segundo | segunda |
| 3rd | terceiro | terceira |
| 4th | quarto | quarta |
| 5th | quinto | quinta |
| 6th | sexto | sexta |
| 7th | sétimo | sétima |
| 8th | oitavo | oitava |
| 9th | nono | nona |
| 10th | décimo | décima |
| 11th | décimo primeiro | décima primeira |
| 12th | décimo segundo | décima segunda |
| 20th | vigésimo | vigésima |
| 30th | trigésimo | trigésima |
| 40th | quadragésimo | quadragésima |
| 50th | quinquagésimo | quinquagésima |
| 100th | centésimo | centésima |
| 1000th | milésimo | milésima |
| 1 000 000th | milionésimo | milionésima |
Este é o primeiro dia do resto da tua vida.
This is the first day of the rest of your life.
Sentámo-nos na segunda fila.
We sat in the second row.
É a terceira vez que te telefono.
It's the third time I'm calling you.
Moro no quarto andar.
I live on the fourth floor.
Ela ganhou o nono concurso seguido.
She won the ninth contest in a row.
No décimo aniversário da empresa houve uma festa.
On the company's tenth anniversary there was a party.
Compound ordinals
For ordinals between decades, both parts agree in gender:
A vigésima primeira edição do festival é este ano.
The twenty-first edition of the festival is this year.
Ele é o quadragésimo sexto presidente dos Estados Unidos.
He is the forty-sixth president of the United States.
Ordinals are rare above 10 — cardinals substitute
In practice, Portuguese uses ordinals readily up to about décimo (10th). Beyond that, especially in chapter numbers, page numbers, centuries, editions, and kings, cardinals often replace ordinals — especially after the noun.
o capítulo vinte
chapter twenty (more natural than 'o vigésimo capítulo')
a página cinquenta e três
page fifty-three
o século vinte
the twentieth century (cardinal after noun is the default)
o século XXI
the twenty-first century (read: 'século vinte e um')
D. João II
King João II (read: 'dom João segundo' — ordinal up to 10; 'dom João doze' for the 12th if such existed)
For royal names, ordinals are used up to the tenth (D. João V = quinto, D. João X = décimo), and cardinals from the eleventh upward. Most readings of dates, centuries, and chapter numbers use cardinals after the noun.
Numerals with articles
Numerals combine with articles in predictable ways.
Definite article + cardinal
Os dois irmãos estudam em Coimbra.
The two / both brothers study in Coimbra.
As três irmãs moram em Lisboa.
The three sisters live in Lisbon.
Os cinco finalistas são muito talentosos.
The five finalists are very talented.
The fixed order is article + numeral + noun. Note how os dois (the two) is the everyday alternative to ambos (both) — see Ambos.
Definite article + ordinal
A primeira vez que te vi, estavas a ler.
The first time I saw you, you were reading.
O segundo andar está à venda.
The second floor is for sale.
Os terceiros classificados também recebem um prémio.
The third-place finishers also get a prize.
Indefinite uns/umas + cardinal — approximate quantities
Uns / umas + a cardinal gives an approximate number — "about, around, some." The numeral typically does not agree (other than when it has an intrinsic gender, like dois/duas).
Vieram uns vinte convidados à festa.
About twenty guests came to the party.
A viagem demora umas três horas.
The trip takes about three hours.
Custou uns cinquenta euros.
It cost around fifty euros.
Tem uns trinta e cinco anos.
He's about thirty-five years old.
Observe that uns or umas agrees with the noun (plural), and the cardinal follows. For feminine nouns, use umas: umas três horas (about three hours), umas vinte pessoas (about twenty people).
Havia umas vinte pessoas à espera.
There were about twenty people waiting.
Numerals with possessives
os meus dois filhos
my two children
as minhas três irmãs
my three sisters
os nossos cinco melhores alunos
our five best students
Fixed order: article + possessive + numeral + noun. See Determiners Overview for the complete stacking order.
Numerals with todos / ambos
todos os três amigos
all three friends
os três amigos todos
all three friends (emphatic)
ambos os dois casos
redundant — 'ambos' already means 'the two'; use one or the other
Ambos already conveys "the two," so stacking it with dois is redundant. Pick one: ambos os casos or os dois casos.
Years, centuries, dates
Nasci em mil novecentos e noventa.
I was born in 1990.
Estamos em dois mil e vinte e seis.
We are in 2026.
O século vinte foi marcado por duas guerras mundiais.
The twentieth century was marked by two world wars.
No dia trinta e um de dezembro.
On the thirty-first of December.
Notice: the first day of the month is traditionally primeiro in PT-PT (no dia primeiro de janeiro), though um is also widely heard and accepted (no dia um de janeiro). For all other days, use cardinals.
Fractions
Fractions use ordinals for the denominator. Meio / meia (half) agrees in gender: meia hora, meio quilo.
um terço
one third (1/3)
três quartos
three quarters (3/4)
Bebi meia garrafa de vinho.
I drank half a bottle of wine.
Common Mistakes
❌ Tenho dois irmãs.
Agreement error — 'irmãs' is feminine plural, so 'duas'.
✅ Tenho duas irmãs.
I have two sisters.
❌ Convidei duzentos pessoas.
Agreement error — 'pessoas' is feminine, so 'duzentas'.
✅ Convidei duzentas pessoas.
I invited two hundred people.
❌ A empresa vale um bilhão de euros.
Brazilian spelling — PT-PT is 'bilião' and means 10¹², not 10⁹.
✅ A empresa vale mil milhões de euros.
The company is worth one billion euros (10⁹). (PT-PT)
❌ Vivo em o quarto andar.
Missing contraction — 'em + o' = 'no'.
✅ Vivo no quarto andar.
I live on the fourth floor.
❌ No dia vinte-primeiro de maio.
Wrong form — compound ordinals are written separately: 'vigésimo primeiro'; but cardinals are more natural for day-numbers after the first: 'dia vinte e um'.
✅ No dia vinte e um de maio.
On the twenty-first of May.
❌ Dois mil vinte e cinco.
Missing 'e' — PT-PT uses 'e' between orders of magnitude.
✅ Dois mil e vinte e cinco.
Two thousand and twenty-five (2025).
❌ Cem e vinte euros.
For compound hundreds, use 'cento', not 'cem'.
✅ Cento e vinte euros.
One hundred and twenty euros.
❌ A primeiro edição do livro.
Agreement error — 'edição' is feminine, so 'primeira'.
✅ A primeira edição do livro.
The first edition of the book.
❌ O país tem trinta bilhões de habitantes.
Catastrophically wrong in PT-PT (would mean 3 × 10¹³ people — more than exists on Earth) — use 'mil milhões' for 10⁹.
✅ A Terra tem cerca de oito mil milhões de habitantes.
Earth has about eight billion inhabitants.
Key Takeaways
- Cardinals are mostly invariable. The exceptions are um/uma, dois/duas, and the hundreds (duzentos/duzentas etc.).
- Ordinals always agree in gender and number: primeiro/primeira/primeiros/primeiras.
- Compound numerals use e between orders of magnitude: cento e vinte, dois mil e vinte e cinco, trezentos e cinquenta e nove.
- Cem vs. cento: cem is a round hundred; cento appears in compounds (cento e um).
- CRITICAL PT-PT vs. BR: um bilião (PT-PT) = 10¹² (a trillion in English). Um bilhão (BR) = 10⁹ (a billion in English). For 10⁹ in PT-PT, say mil milhões.
- Ordinals above 10 are often replaced by cardinals after the noun in everyday PT-PT: o capítulo vinte, o século vinte e um.
- Uns / umas + cardinal gives an approximate quantity: uns vinte euros (about twenty euros).
- First of the month: primeiro is traditional but um is also common in PT-PT (dia primeiro or dia um).
- Fractions: meio/meia for half (agrees in gender); ordinals for other denominators: um terço, dois quintos.
- Numerals combine with articles, possessives, and other determiners in the fixed order article + possessive + numeral + noun.
Related Topics
- Determiners in Portuguese: An OverviewA1 — What determiners are, the families of determiners in European Portuguese, and how they combine with nouns — a map of the group.
- The Indefinite Article: Forms and UsesA1 — The four forms of the Portuguese indefinite article (um, uma, uns, umas), their uses for introducing new referents, and where Portuguese drops the article that English keeps.
- The Definite Article: Forms and Basic UsesA1 — The four forms of the Portuguese definite article (o, a, os, as) and the contexts where European Portuguese requires it — including several where English leaves it out.
- Ambos: 'Both'B1 — Using ambos/ambas to express 'both' in European Portuguese — including the obligatory article, the common colloquial alternative 'os dois / as duas', and the comparison with Spanish cognates.
- Indefinite Determiners: algum, nenhum, qualquer, cada, todo, vário, certoA2 — A guided tour of the Portuguese indefinite determiners — words that quantify or identify without being definite: algum, nenhum, qualquer, cada, todo, vário, certo, muito, pouco, outro, mesmo, tanto, and the todo/tudo distinction.