Days of the week and months in Spanish: the lowercase rule

In Spanish the days of the week are lunes, martes, miércoles, jueves, viernes, sábado and domingo, and the months run enero, febrero, marzo, abril, mayo, junio, julio, agosto, septiembre, octubre, noviembre and diciembre. All nineteen stay lowercase inside a sentence, the one habit English speakers have to unlearn, since English capitalizes Monday and January while Spanish saves capitals for sentence starts and proper names. Here is the full set with native audio, the small grammar around it, and the way Spanish writes the date.

The nineteen words, with audio

These are the days and months from the time theme of Vocabcord's A1 Spanish set, 625 phrases with native-speaker audio, graded to the CEFR scale. The wider corpus behind these guides holds 33,233 phrases across six learner languages paired with English, from A1 to C2; the corpus statistics page breaks those numbers down. Tap the play button on any row to hear the word.

The capitalization rule English speakers miss

English writes Monday and January with capitals because it treats them as proper nouns. Spanish files the days and months alongside ordinary words like semana (week) and mes (month), so in running text they all stay lowercase: nos vemos el jueves (see you on Thursday), mi vuelo sale el 12 de octubre (my flight leaves on October 12). A capital appears only where any word would get one, at the start of a sentence or in a heading, and that convention holds across the whole Spanish-speaking world. The table above capitalizes each word because every entry opens its own row; the moment one lands mid-sentence, drop it to lowercase. Write a capitalized Lunes in the middle of a sentence and it reads as a typo to a Spanish eye, the mirror image of a stray lowercase monday in English.

lunes to domingo: how the days behave

Spanish calendars begin the week on lunes, so a printed month runs Monday through Sunday. To say on a day, skip the preposition and reach for the article: el lunes means on Monday, and the plural los lunes means on Mondays, week after week. The five weekdays already end in s and keep the same shape in the plural (el martes, los martes), while sábado and domingo add one (los sábados, los domingos). If you want a memory hook, the weekdays carry sky names: lunes comes from Luna the moon, martes from Mars, miércoles from Mercury, jueves from Jupiter, and viernes from Venus. Sábado traces back to the Sabbath, and domingo to the Latin for the Lord's day.

enero to diciembre: the months

The months are the friendliest corner of the Spanish calendar, because most of them look like their English cousins: abril, octubre, noviembre. Learn the odd one out, enero for January, and the set is nearly free. The grammar stays light too. All twelve are masculine, and you will usually meet them after en or de: en agosto (in August), a finales de junio (at the end of June). The bare month after en is the whole pattern; nobody says en el agosto. One more thing worth pinning: the names travel across hemispheres while the seasons flip, so enero sits in the middle of winter in Madrid and the middle of summer in Buenos Aires.

How Spanish writes the date

Build a date with el plus the number, then de, then the month: el 5 de agosto. Add the year with a second de: el 5 de agosto de 2026. Plain cardinal numbers cover every day of the month, though the first of the month often takes el primero across Latin America while Spain leans on el uno. In digits the day comes before the month, so 05/08/2026 reads as the fifth of August; if you grew up on month-first dates, give every short date a second look. To ask what day it is, use ¿Qué día es hoy? and answer with the bare day: hoy es miércoles. If the numbers from 1 to 31 still feel wobbly, the Spanish numbers guide runs from zero to a hundred.

Let the calendar do the reviewing

Calendar words arrive with a built-in review schedule: the days return every week and the months every year, so each real plan you make in Spanish counts as a repetition. Say el viernes to yourself as the weekend gets close, and en septiembre when you book the trip. Vocabcord covers the stretches between plans. Every time you plug in your phone, one phrase plays out loud, drawn from a corpus frequency-ranked against the New General Service List and spaced so a word returns right before it fades. You never schedule a session or remember to open an app; plugging in is the trigger, and words like miércoles settle in on their own.

Common questions

What are the days of the week in Spanish?

Monday is lunes, Tuesday martes, Wednesday miércoles, Thursday jueves, Friday viernes, Saturday sábado, and Sunday domingo. Spanish calendars start the week on lunes, and all seven names stay lowercase inside a sentence.

What are the months in Spanish?

enero (January), febrero (February), marzo (March), abril (April), mayo (May), junio (June), julio (July), agosto (August), septiembre (September), octubre (October), noviembre (November) and diciembre (December). All twelve are masculine and stay lowercase in running text.

Why are the days and months lowercase in Spanish?

Spanish treats them as common nouns, the same class as words like semana (week), so they take a capital only where any other word would: at the start of a sentence or in a title. Write nos vemos el viernes (see you on Friday) and llego en marzo (I arrive in March).

How do you say the date in Spanish?

Use el + number + de + month: el 5 de agosto is the fifth of August. Add the year with another de: el 5 de agosto de 2026. In digits Spanish puts the day first, so 05/08/2026 means the fifth of August rather than May 8.

How do you say 'on Monday' in Spanish?

El lunes. The definite article does the work English gives to the word on: nos vemos el lunes means see you on Monday. For something that repeats every week, switch to the plural: los lunes means on Mondays.