Using ordinal numbers with events, celebrations, anniversaries in Spanish

Ordinal numbers describe an order/rank. They are often used in Spanish to indicate the position of an event, a celebration or an anniversary within a series, i.e. ones that take place regularly (monthly, annually...). 

To learn about Spanish ordinal numbers from 1st to 10th see Forming ordinal numbers in Spanish (1st, 2nd, 10th...)

Learn about Spanish ordinal numbers (11th to 100th)

Here is a table of representative Spanish ordinal numbers from 11th to 100th. 

	English	Spanish
11th	eleventh	undécimo / décimo primero / decimoprimero
12th	twelfth	duodécimo / décimo segundo / decimosegundo
13th	thirteenth	décimo tercero / decimotercero
14th	fourteenth	décimo cuarto / decimocuarto
15th	fifthteenth	décimo quinto / decimoquinto
16th	sixthteenth	décimo sexto / decimosexto
17th	seventeenth	décimo séptimo / decimoséptimo
18th	eighteenth	décimo octavo / decimoctavo
19th	nineteenth	décimo noveno / decimonoveno
20th	twentieth	vigésimo
21st	twenty-first	vigésimo primero / vigesimoprimero
22nd	twenty- second	vigésimo segundo / vigesimosegundo
23rd	twenty-third	vigésimo tercero / vigesimotercero
30th	thirtieth	trigésimo
31st	thirty-first	trigésimo primero
32nd	thirty-second	trigésimo segundo
33rd	thirty-third	trigésimo tercero
40th	fortieth	cuadragésimo
41st	forty-first	cuadragésimo primero
50th	fiftieth	quincuagésimo
60th	sixtieth	sexagésimo
70th	seventieth	septuagésimo
80th	eightieth	octogésimo
90th	ninetieth	nonagésimo
100th	hundredth	centésimo

 

Agreement in Spanish ordinal numbers

Ordinal number are adjectives and as such, they must agree in gender and number with the noun they accompany (-o, -a, -os, -as): vigésimo aniversario, vigésima edición, vigésimos aniversarios, vigésimas ediciones

When the ordinal number is a compound one (two words) both numbers must agree in gender with the noun:

When the ordinal number is a simple one (one word only) then the agreement shows in the last letter only:

 

 

Extra name for 11th and 12th

For 11th and 12th there is an extra name: undécimo and duodécimo.

 

Written accent loss in Spanish ordinal numbers

When the single word ordinal is used, e.g. decimoprimero, vigesimosexta, vigesimocuarta..., the written accent from the first ordinal number is lost: décimoprimero

 

Only compound word from 30th

For the first two tens of the ordinal numbers (tens and twenties) the simple and compound spelling are permitted (décimo cuarto or decimocuarto, for example) but from 30th only the compound form (two separate numbers) is permitted: 

 

General loss of "o" for octavo

When using an ordinal number involving "octavo", and it's written in one word, the recommended spelling is to use only one "o" at the point where the compound word joins e.g. decimoctavo, vigesimoctavo, thus avoiding the repetition of the letter "o" (decimooctavo, vigesimooctavo).

 

Shorter forms of 1st and 3rd

The shorter forms of 1st and 3rd (primer, tercer) need to be used as usual, for example: el vigesimoprimer aniversario, el decimotercer concurso. See Primero and tercero become primer and tercer before a noun (Spanish apócope)

Ordinal numbers abbreviations in Spanish: la letra volada

In English, ordinal numbers are marked with st, nd, rd or th after the number, in Spanish we use superscript (called "letra volada") for the abbreviation of the ordinal that we place after the digit. We use º with a masculine noun, and we use ª with a feminine noun, and ^er for 1^er and 3^er (primer / tercer).

It's also necessary to use a full stop/period between the number and the "letra volada": 

 

Roman numerals used and read as ordinal numbers

Sometimes Roman numerals are also used to talk about certain events. In this case, the Roman numeral is placed before the noun and it's read as an ordinal number. For example:

 

Careful! Not all Roman numerals are used and read the same way. See also How to express centuries in Spanish with Roman numerals and more information about Roman numerals here in How to use Roman numerals in Spanish

 

For example you can also write and say:

 

See also Expressing fractions in Spanish and Using numbers with nouns in Spanish