When a player's hand needs only one tile to win (tenpai) while the hand is closed (i.e. the player has not called any opponent's discards to makemelds), the player can opt to declareriichi. Thisyaku is often called "reach" because its Japanese name is phonetically similar to the English word.^{[citation needed]}

Conditions after declaration

To make a declaration, the player calls out “riichi”, discards their tile by placing it sideways, and places a 1,000-point stick on the table, as a deposit. From then on, any tile they draw must be automatically discarded if it does not give them a winning hand. In this way, they cannot change the content of their hand in any way (except declaring certain closed quads).

In some rulesets, a player can declareriichi only when there are four or more tiles remaining in the wall. That is, if they cannot draw another tile, they cannot declareriichi. The player is not penalized if drawing another tile is prevented due to opponents making open melds orclosed quads after the declaration.^[1]

If all four players have declaredriichi, a hand ends as anabortive draw. Players show their hands to confirm they aretenpai, or they are penalized withchombo.^[2]

Ura dora ("underneath dora")

When a player wins, any underneathdora indicator tiles are revealed. These are just like regulardora, but the indicator lies beneath thedora tile in the dead wall. The number ofura dora tiles to be revealed is based on how manydora tiles are open viakan calls.

Riichi deposits

The winner of a hand receives all 1,000-pointriichi sticks that are present. In the case of multiple winners, the player closest to the discarding player (moving forward) receives allriichi deposits. If a hand ends in a draw, anyriichi deposits carry over to the next game and are placed near thecounters. The next winner receives thoseriichi deposits. In most cases, if a draw results in ending the game (such as exhaustive draws in the final round with the last dealer not ready to win, or exhaustive draws causing one or more players to reach a negative score), the game immediately ends while allriichi deposits are forfeited.

Claiming ariichi discard

When a player declaresriichi and discards a tile (sideways), an opponent may call that tile for ameld. Theriichi player, on their next turn, places their next discard sideways. Additionally, if ariichi discard tile is called by another player to win, then the would-beriichi declaration is considered incomplete and therefore no forfeiture ofriichi deposit.^[1]

Declaring closed quads

A player declaringriichi may allowed to call a closedquad (kan). This can only happen when they have a triplet in their hand and they draw the fourth tile. Even though the hand remains closed, the quad is still displayed on the table. While inriichi, a quad call must not otherwise change the composition of the hand or itswaits.^[1][2] For example, when a player has, they can declare a closed quad when drawing the fourth. However, when they have waiting for, or, they cannot declare a quad when drawing, because and would no longer be winning tiles.

In general Japanese rules, all seven pairs must be unique, meaning that the same four tiles may not be split into two pairs. Some rules, such as in theKansai region, may accept four of the same tile, but they are not considered a quad.^[3]

TheWorld Riichi Championship as of 2025 and theEuropean Mahjong Association as of 2016 do not include this hand in their rulesets.^[5][6]

Sometimes thepao (包) rule is applied to this hand. If a player claims a discard to make an open quad and then completes their hand with a tile drawn from the dead wall, the hand is considered as a discard instead of self-drawn.

Robbing a closed quad

In most rulesets, a player cannot rob a closed quad, only an open one (i.e. after their opponent has "upgraded" an open triplet to a quad). Some rulesets have an exception: robbing a closed quad is allowed if it's used to complete Thirteen Orphans (in this situation, a limit would be awarded instead of the hand).

While there are certain melds or a set that awardsfu, the hand must be entirely in sequence and its pair is neither a dragon tile, or winds tiles corresponding to the round or seating itself; any triplets, quads, or pairs of such awardfu. Its hand must also be waiting for multiple winning tiles that does not form a pair. For example,^[7] such as having and thus waiting for or. All single-tile "waits" earnfu, namely an "inside wait" (e.g. waiting for a); an "edge wait" (e.g. waiting for a); or waiting to complete any pair.

Combination of no-point hand and self-draw

When the winning hand is a no-point hand, those 2fu from a self-draw are normally waived. Such a hand allows both of these to be stacked.

Some (uncommon) rulesets say that a no-points hand disallow self-drawing. In this case, 2fu are awarded, and only 1han. The rule is called "pinfu–tsumo nashi" (平和自摸無し or 平和ツモなし,pinfu–tsumo invalid), sometimes contracted to "pinzumo nashi" (ピンヅモなし). The opposite rule is called "pinfu–tsumo ari" (平和自摸有り or 平和ツモあり,pinfu–tsumo valid).^[8]

Some rules may not allow the two sets to be the same, i.e. four identical sequences.

The Japanese name of this hand,kokushi musō, means "a peerless distinguished person in a country."^[11] Other names for thisyaku areshīsan yaochū (十三么九) which means "thirteen of smallest numbers and 9's [and honors]," or its abbreviationshīsan yao (十三么).

Depending on the ruleset, this hand can be valued at either ayakuman,baiman, ormangan. In stricter rulesets, this is not considered a hand at all, and requires other hands to win. Some rulesets are laxer as the player can still achieve Blessing of Man after their first turn, if the tile they are calling was their opponent's first discard. Because of these variations, this hand is considered optional.^[13]

Each of the numbered suits may also use special names for this hand:

Pinzu (circles),daisharin – 大車輪 orbig wheels

Sōzu (bamboo),daichikurin – 大竹林 orbamboo forest

Manzu (characters),daisūrin – 大数隣 ornumerous neighbours