Riichi
By Kenji Tanaka · Updated
Definition
The signature declaration of Japanese mahjong, and the yaku the game is named for. With a closed hand in tenpai you announce riichi, stake a 1,000-point stick, and lock your hand in exchange for 1 han plus access to ippatsu and ura dora. From that moment everyone at the table knows you are one tile from winning, and the whole hand changes around that fact.
Riichi
Riichi (立直, りーち) is a declaration in Japanese mahjong announcing that a player’s hand is one tile away from winning (tenpai). By declaring riichi, a player commits 1,000 points and places a riichi stick on the table, locking their hand and earning one han (value point). This mechanic is fundamental to Japanese mahjong and opens access to additional scoring opportunities.
Understanding Riichi
Riichi is both a yaku (scoring hand pattern) and a strategic declaration that fundamentally shapes gameplay. When a player declares riichi, several things occur simultaneously:
The Declaration Process A player may declare riichi only when their hand is tenpai (one tile away from completion) with a closed hand, meaning no melds have been made. The player announces “riichi,” pays 1,000 points from their score, and places a physical riichi stick perpendicular to their discard pile. This stick remains visible throughout the hand and serves as a warning to other players.
Hand Lock Once riichi is declared, the player’s hand becomes locked. They cannot change their winning condition or rearrange tiles. If they draw a tile that doesn’t complete their hand, they must discard that drawn tile immediately; the only exception is declaring a concealed kan that does not change their wait. This inflexibility is the trade-off for riichi’s benefits.
Scoring Value Riichi itself is worth 1 han. Combined with the base hand value (fu), this increases the final score. However, riichi’s primary value lies not in the han itself but in the additional scoring opportunities it enables.
Uradora and Ippatsu Declaring riichi unlocks two powerful bonus yaku:
- Uradora (裏ドラ): Flip-side dora tiles become active when a player wins after declaring riichi. These hidden bonus tiles can significantly increase hand value.
- Ippatsu (一発): If a player wins within one go-around of declaring riichi, before their own next discard and with no calls in between (including ron on an opponent’s discard), they earn ippatsu, an additional 1 han.
Dama vs. Riichi
A strategic choice exists between declaring riichi and playing “dama” (playing silently without declaring). Dama means keeping your tenpai status hidden while foregoing riichi’s benefits. Dama is safer because opponents don’t know you’re close to winning, but you lose uradora and ippatsu opportunities. Riichi is more aggressive and rewarding but telegraphs your danger to the table.
Furiten Consideration
A player in furiten (having discarded a tile they need to win) may still declare riichi, but they can only win by tsumo, not ron. Passing up a winning tile after declaring riichi also makes furiten permanent for that hand.
Riichi in practice
A player holds a closed hand needing only a 5-pin to win. They have no melds and are certain of their tenpai. They declare riichi, pay 1,000 points, and place a riichi stick. On the next turn, they draw a 5-pin and win. Because they declared riichi and won on the next turn, they score ippatsu (1 han). Additionally, uradora tiles flip, potentially adding more han to their final score. Their hand now scores significantly higher than if they had played dama.
Related Terms
Tenpai
聴牌
Tenpai is the ready state: one tile from a complete hand. It is the requirement for declaring riichi, and it is worth points at an exhaustive draw, when tenpai players collect from noten. The tiles that finish the hand are the wait (machi), in shapes running from the wide ryanmen to the narrow tanki. Distance from tenpai is counted in shanten, and the entire efficiency game is reaching 0 faster and wider than the rest of the table.
Ippatsu
一発
Win within one uninterrupted go-around of declaring riichi and you add ippatsu, a 1-han bonus. Any pon, chii, or kan between your riichi and your win cancels it. The name means one shot, and together with ura dora it is a big part of why riichi hands spike in value.
Uradora
裏ドラ
Uradora are the hidden dora revealed only on a riichi win, flipped from beneath the regular indicators. They are riichi's lottery ticket: pure variance that can turn riichi-plus-nothing into a mangan. Declared kans add matching ura-kandora underneath their indicators too. Only riichi hands ever see them, which is a standing argument for declaring instead of sitting damaten.