Spanish adjective agreement: matching gender and number

Adjectives with four forms

If the masculine singular ends in -o, the adjective has all four forms: -o, -a, -os, -as.

Un carro nuevo, una casa nueva, unos carros nuevos, unas casas nuevas. The adjective doesn’t care what it means or where it sits — it takes its shape from the noun it belongs to, and in Spanish it usually sits after that noun.

This group includes most descriptive adjectives you’ll use daily: caro, barato, largo, corto, alto, bajo, frío, seco, tranquilo, cansado.

Adjectives with two forms

If the masculine singular ends in -e, in -ista, or in a consonant, gender doesn’t change anything. Only the plural does. Two families of consonant endings escape this rule and do take a feminine: the ones in -or, -ón and -án (trabajador → trabajadora, dormilón → dormilona, holgazán → holgazana) and the nationalities, which get their own section below.

Un problema grave / una situación grave. Un cliente realista / una clienta realista. Un examen difícil / una prueba difícil. Plural: graves, realistas, difíciles.

Forming that plural follows three rules. Ends in a vowel, add -s: verde → verdes. Ends in a consonant, add -es: fácil → fáciles, joven → jóvenes. Ends in -z, swap it for -ces: feliz → felices, capaz → capaces.

Those are the same three rules nouns follow, so once you have the plural of Spanish nouns down, the adjective plural comes for free: papeles azules, luces verdes.

Watch the written accent while you’re at it: it comes and goes to keep the stress where it already was. Joven picks one up in the plural (jóvenes), while inglés and alemán drop theirs: ingleses, alemanes.

Nationalities, which break the consonant rule

Nationality adjectives ending in a consonant do have a separate feminine, which makes them the main exception to the section above.

Español → española, francés → francesa, alemán → alemana, inglés → inglesa, japonés → japonesa, portugués → portuguesa. Plurals: españoles, españolas, franceses, francesas.

The ones ending in -e or -a behave normally and don’t change for gender: estadounidense, canadiense, nicaragüense, belga. So un compañero canadiense and una compañera canadiense are both correct. Those ending in stressed -í don’t change for gender either, but their plural takes -es or -s: israelí → israelíes / israelís.

And nationalities are written in lowercase in Spanish: soy estadounidense, not Estadounidense. The same goes for languages, days and months; the list of what Spanish keeps lowercase is longer than most learners expect, and the demonym for every country is on the nationalities in Spanish page.

Reference chart

Mixed groups, shortened forms and other edge cases

A masculine and a feminine noun together take the masculine plural. El contrato y la factura están firmados. Mi hermano y mi hermana son altos. It doesn’t matter which one comes first or how many of each there are — one masculine noun in the group is enough.

Some adjectives lose their ending in front of a singular noun. Bueno, malo, primero and tercero drop the -o before a masculine singular: un buen día, mal tiempo, el primer trimestre. Grande becomes gran before any singular noun, masculine or feminine: un gran problema, una gran oportunidad.

A few color words don’t move at all. When the color comes from a noun — naranja, rosa, violeta — it usually stays fixed: unas camisas naranja. And when you say color café or color crema, nothing changes either.

The pairs where the ending changes the meaning

Position and shortening aren’t decoration here. They change what the sentence says.