What Do the Letters on Madrid Taxis Mean?

A Fun Spanish Tip for Travelers & Learners

If you’ve ever visited Madrid or you’re planning a trip to Spain, you’ve probably noticed something curious on the back of many taxis: a single letter printed near the rear of the car.

Most tourists don’t think twice about it, but if you’re someone who loves learning about Spanish culture—or you’re studying Spanish—this small detail is actually pretty interesting!

The Letter on the Back of Madrid Taxis Has a Purpose

That little letter indicates the driver’s mandatory rest day. The Madrid City Council introduced this system to make sure there are always enough taxis available and that drivers take a regular day off.

So, when you see a taxi with a letter like J, M, L or V, it’s not random—it tells you which day of the week that taxi is not allowed to operate.

Days of the Week in Spanish (and the Taxi Letters)

Here’s how the letters correspond to the days:

English DaySpanish DayTaxi LetterMondayLunesLTuesdayMartesMWednesdayMiércolesX*ThursdayJuevesJFridayViernesVSaturdaySábadoS (sometimes shown)SundayDomingoD (optional in some fleets)

* Why “X” for Wednesday? Because both martes and miércoles begin with M. To avoid confusion, Wednesday uses the second letter in the Spanish word: X.

Example: What Does the Letter “J” Mean?

If you see a taxi in Madrid with the letter J on the back, that means the driver’s day off is:

Jueves ➝ Thursday

So that taxi won’t be working on Thursdays.

Why This Is Interesting (and Useful!)

Whether you’re:

• A tourist visiting Madrid

• Learning Spanish vocabulary

• Curious about Spanish culture

• Preparing for travel to Spain

• Practicing the days of the week in Spanish

…this little cultural detail is a fun way to connect language with real life.

You can even use it as a mini Spanish lesson when you're walking around the city:

• See an L? Think lunes (Monday).

• Spot an X? That's miércoles (Wednesday)!

• Notice a V? You guessed it—viernes (Friday).