How to Use the Days of the Week in French

1. “Lundi” vs “Le lundi” - the Habitual Article Rule

This is the single most common grammar error beginners make with French days of the week, and once you understand the logic it becomes intuitive. The rule is simple: use a bare day name for a specific, one-off occasion, and add “le” before the day to express a recurring habit.

In English, we distinguish these with context or phrasing: “I will see you Monday” (specific) vs “I work on Mondays” or “I work on Monday” (habitual). French makes the distinction grammatically, with the definite article carrying the habitual meaning. The article “le” essentially means “every” when placed before a day name.

2. Capitalisation - French Days Are Always Lowercase

In French, days of the week are common nouns, not proper nouns. They are written in lowercase unless they appear at the very beginning of a sentence. This is unlike English, where Monday, Tuesday, Wednesday etc. are always capitalised regardless of their position in the sentence.

Exception: Capitalise the day if it is the first word of a sentence: “Lundi, je pars en vacances.” (Monday, I leave for the holidays.) The same rule applies to all French nouns - sentence-initial position triggers capitalisation.

3. Writing Dates in French

French date format differs significantly from American English. The key rules: day of the week first (optional but common), then the number, then the month in lowercase, then the year. No commas. No ordinals except for the 1st of the month, which uses “1er” (premier). The numeric format is DD/MM/YYYY, the reverse of US convention.

4. Gender - All Days Are Masculine

All seven French days of the week are masculine nouns. This affects which articles and adjectives you use with them. While this is a simple rule to state, it has practical consequences when forming sentences.

5. Prepositions and Relative Time Expressions

French uses adjectives and phrases placed after the day name to express relative time (next, last, every other). Note that in French, these modifiers come after the day name, unlike English where they precede it: “lundi prochain” (next Monday), not “prochain lundi”.