Sequence of Play

During play, the letter tiles are kept in an opaque cloth bag or face down on a flat surface. At the beginning of the game, and after each turn until the bag is empty, players draw tiles to replenish their racks with seven tiles, from which they will make plays.

At the beginning of a player's turn, they will have seven letter tiles in their rack from which to choose a play. A player's rack is kept concealed from the other players. On their turn, they have the option to:

1. Pass, forfeiting the turn and scoring nothing;
2. Exchange one or more tiles for an equal number from the bag, scoring nothing (this option is allowed only when at least seven tiles remain in the bag); or
3. Form a play on the board, adding its value to the player's cumulative score.

A proper play uses any number of the player's tiles to form a single continuous word ("main word") on the board, reading either left-to-right or top-to-bottom. The main word must either use the letters of one or more previously played words, or else have at least one of its tiles horizontally or vertically adjacent to an already played word. If words other than the main word are newly formed by the play, they are scored as well, and are subject to the same criteria for acceptability. When no words have yet been formed on the board, a player must form a word (of at least two letters, extending horizontally or vertically), which covers the centre cell H8.

A blank tile may be designated by the player as any letter; it remains as that letter thereafter for the rest of the game. As a letter, it scores no points (even doubled or tripled) regardless of what letter it is designated, but its placement on a double-word or triple-word cell does cause the appropriate premium to be scored for the word in which it is used. While not part of official or tournament play, a common "house rule" allows players to "recycle" blank tiles by later substituting the corresponding letter tile.

After playing a word, the player draws letter tiles from the bag to replenish their rack to seven tiles. If there are not enough tiles in the bag to do so, the player takes all of the remaining tiles.

After a player plays a word, their opponent may choose to challenge any or all the words formed by the play. If any of the words formed are found to be unacceptable, the play is removed from the board, the player returns the newly-played tiles to his rack, and their turn is forfeited. Penalties for unsuccessfully challenging an acceptable play vary within club and tournament play.

Within North American rules, the game ends when:

1. One player plays every tile in his rack, and there are no tiles remaining in the bag (regardless of the tiles in his opponent's rack); or
2. When six successive scoreless turns have occurred and at least one word is on the board.

In the first case, the player who "goes out" receives a bonus of twice the point value of their opponent's remaining tiles. Scoreless turns can occur when a phoney is challenged off the board, when a player passes, when a player exchanges tiles, or when a word consists only of blank tiles. This rule varies slightly in international play.