Spanish ordinal numbers: primero to décimo, and stop

Course · Unit: Numbers CEFR A1 Reviewed by Jhoslyn Updated 2026-09-12

Draft copy. Every claim needs a native-speaker check before publishing — the byline is what makes this citable, so it has to be earned.

The ten you need

They are adjectives, so they agree: el primer día, la primera vez, los primeros capítulos, las primeras lluvias.

They normally go in front of the noun — el quinto día — though you will see them behind it in set phrases like la calle octava and in formal writing.

Primero and tercero lose their o

Before a masculine singular noun only:

• el primer piso — but la primera vez
• el tercer día — but la tercera hija
• el primero en llegar — standing alone, the full form comes back

No other ordinal does this. El segundo piso, el cuarto piso, el noveno piso all keep their ending.

Past ten, Spanish stops bothering

This is the part course books bury and speakers rely on. Undécimo, duodécimo, vigésimo primero, trigésimo — these exist, they are in the dictionary, and almost nobody says them out loud. From eleven upwards Spanish switches to the ordinary counting numbers:

Monarchs follow the same line: ordinal up to ten, cardinal after. Isabel II is Isabel segunda; Luis XIV is Luis catorce.

The one that catches everyone is the century. You are living in el siglo veintiuno. Say el vigésimo primer siglo and you will be understood, and you will also sound like a translated legal document.

Note the number stays in its plain cardinal form and does not agree: el capítulo veinte, la página treinta.

Dates: only the first is an ordinal

Latin America uses primero for the first of the month and cardinals for everything else.

• el primero de enero — the 1st of January
• el dos de enero — the 2nd
• el quince de agosto — the 15th

There is no el segundo de enero. Spain says el uno de enero for the first; in Peru it is el primero, and that is what you should say here.

Floors, and a difference that matters in Lima

In Peru the ground floor is el primer piso. The floor above it is el segundo piso. There is no planta baja in ordinary Peruvian usage — that is Spain.

So if someone tells you está en el segundo piso, that is one flight up from the street, not two. In a lift the buttons usually run 1, 2, 3 from the entrance, and sótano is the basement.

Useful alongside it:

• ¿En qué piso está? — which floor is it on?
• Está en el tercer piso.
• el ascensor — the lift. Not el elevador, which is Mexican

Primero as a sequencing word

Primero, segundo and tercero also work as plain adverbs meaning “first, second, third” when you are listing steps. No agreement, no noun:

Primero, me baño. Segundo, desayuno. Tercero, salgo a trabajar.

This is how recipes, instructions and explanations are structured, and it is worth having ready before you need any ordinal above three.

Try it

1. It’s on the first floor (Peruvian counting: street level).
2. The third chapter.
3. The 21st century.
4. The 1st of May.

→ 1 Está en el primer piso · 2 el tercer capítulo · 3 el siglo veintiuno · 4 el primero de mayo.

Next

The counting numbers themselves, plus telling the time and saying dates.

→ Spanish numbers, time and dates

Topics AdjectivesPeruvian Spanish