¡Allá tú!

The program begins by each contestant being described by name and region (usually the newest contestant to replace the one who played last episode receives a special presentation), and then they answer a qualifying question, usually about statistics (i.e. "What percentage of the Spanish elderly have used the Internet? 1: 6%, 2: 26%, 3: 69%").[3] Out of those who answered correctly, one is drawn, who proceeds to the podium.

Before the game begins, the contestant picks one of the 22 boxes (26 cases for special episodes). Each box contains a different amount of money, from €0.10 to €300,000.

In the main game, the contestant's objective is to find out what their box contains by removing the boxes of the other 21 contestants (or 25 for specials): when each box is selected, the card with the box's value on is shown to the camera before the value of the card is out of play, and the display shows the amounts remaining.

At various points in the game, La Banca (The Banker) makes a phone call to the host and makes the contestant a cash offer to purchase their box and for the contestant to quit the game based on the value of the boxes left. The contestant then decides whether to accept the offer and end the game or decline the offer and continue playing.

In the first round the contestant opens five boxes, four in the second, three in the third and then two each in the fourth, fifth, sixth and seventh.

One player plays for the entire episode (except for the million-euro specials, which were longer and featured two players per episode). When their episode finishes, a new contestant replaces them in the wings.

In 2005, the money values were modified slightly, and the top prize was increased to €600,000 (though the contestant's winnings were split with a phone-in contestant and taxed).

The 2023 revival has two players on each episode, as the show is now a weekly prime time format with a runtime similar to that of the 2006 million-euro specials, and introduces two new elements to the gameplay:

• El pulsador de la oferta extra (The Extra Offer Buzzer): Before hearing the first offer, the player is asked to guess how much money the Banker has offered to purchase the box. If the player guesses correctly or is off by €1,000 or less, they have the option to activate the buzzer and request one additional offer from the Banker, aside from the ones that happen when specific numbers of boxes remain, at any time in the game.
• La comunidad de la suerte (The Lucky Region): The Banker can offer the player to abandon the game if it isn't going well, and instead try to guess which Spanish region is written in a smaller, silver box. The player wins €30,000 for guessing correctly in the first attempt and €10,000 for guessing correctly in the second attempt, but the player leaves without any money if neither guess is correct.[4]

NOTE: Some small values are often replaced with joke prizes (except for the million euro specials).

In 2011, Box 23 ("The Green Box") could contain one of the following amounts: