1. Introduction
Riichi is the modern Japanese variant of mahjong, a four-player game played with tiles. The object of play is to complete a winning hand; the ultimate object of the game is to accumulate the most points from winning hands. It does not matter how many hands each player has won — the accumulated score alone determines the winner (3, 3.7).
These are the rules of the European Mahjong Association. The EMA riichi rules exist so that riichi is played and taught the same way across Europe, and so that players meeting at a table already share the same etiquette and rules. They also serve as a rule set that can be taught to beginners and used by social players in clubs.
The first edition was written for the first European Riichi Championship in Hannover, Germany in 2008. It was revised in 2012 to move closer to current Japanese riichi rules, again in 2016 to move closer to the World Riichi Championship rules, and again in 2025. This 2025 revision improves clarity, makes minor rule changes to align further with WRC rules, and is based on a large survey of EMA-certified riichi referees.
Riichi is one of the three official mahjong rule sets used by the Mahjong International League, a member of the International Mind Sports Association.
2. Components
The Tiles
- There are 34 basic tile types. A full set contains four identical tiles of each type, giving 136 tiles in play (1, 1.3)
- Three suits — circles (pinzu), bamboo (sōzu) and characters (manzu) — each numbered one to nine (1.1)
- The ones and nines of each suit are called terminals (1.1)
Honours
- Seven honour tile types: four winds and three dragons (1.2)
- The winds are ordered east-south-west-north; the dragons are ordered white-green-red (1.2)
- The white dragon's design varies between sets — usually blank, or decorated with a blue frame (1.2)
Tiles Not Used
- Sets may include flower, season or joker tiles. These are not used in riichi mahjong (1.3)
- Japanese sets often include red fives, each normally worth one han. Red fives are not used under EMA riichi rules (1.3)
Other Equipment
- A marker for the round wind, and point sticks worth 100, 1,000, 5,000 and 10,000; a stick of a different colour may serve as 500 (1.4)
- Point sticks double as counters and riichi bets (1.4)
- Players begin with 30,000 points each (1.4)
- At least two dice (1.4)
3. Setup
Seats and Winds
- Four players, each associated with a seat wind. East is the starting player; South sits at East's right, West across from East, North at East's left (2.1)
- The counter-clockwise order east-south-west-north does not correspond to compass directions (2.1)
- Over a full game each player is East at least twice (2.1)
- East is the round wind when the game begins; when the starting East becomes East again, the south round begins and a wind marker is flipped (2.2)
- Seats are decided by drawing lots with one tile of each wind, unless a tournament schedule fixes them. The player who shuffled picks last, and at least three players must be present for the draw (2.3)
Building and Breaking the Wall
- Tiles are shuffled face-down; each player builds a wall seventeen tiles long and two tiles high, and the four walls are pushed together into a square (2.4)
- East rolls two dice and counts that number of players counter-clockwise, starting with themselves; that player's wall is broken, counting from their right the same number of tile stacks (2.5)
The Dead Wall and Dora
- The first seven tile stacks counter-clockwise from the break form the dead wall — fourteen tiles (2.6)
- The four tiles closest to the break are replacement tiles; the next ten are the dora indicator, the kan dora indicators and the ura dora indicators (2.6)
- The dora indicator is revealed by counting three tile stacks into the dead wall from the break and turning the top tile over (2.7)
- The dora is the next tile after the indicator: for a suit tile the following number, with 9 pointing to 1; for dragons red→white→green→red; for winds east→south→west→north→east (2.7)
The Deal
- East draws the first four tiles after the break, then South, West and North take four each, repeating until every player holds twelve tiles (2.8)
- East then takes two tiles (the top tiles of the first and third stacks) and the others one each, so East starts with fourteen tiles and everyone else with thirteen (2.8)
- Tiles are taken clockwise even though turns proceed counter-clockwise (2.8)
- The dice are placed at East's right where possible, so it is always clear who is East (2.8)
4. Gameplay
Structure of a Game
- A full game is two rounds — the east round and the south round — each of at least four hands, during which each player is East in turn (3.1)
- A hand ends when a player declares a win or an exhaustive draw occurs (3.1, 3.4)
- A turn begins when a player draws from the wall or claims a set, and ends when they discard (3.1)
What Wins
- A complete hand is four sets and a pair. A set is a sequence, triplet or quad (3.2)
- A sequence is three consecutive tiles of the same suit — never dragons or winds, and it does not wrap: 8-9-1 and 9-1-2 are not sequences (3.2)
- A triplet is three identical tiles, a quad four, a pair two (3.2)
- A winning hand must be complete and hold at least one yaku (scoring pattern) (3.2, 4.2)
- Seven Pairs and Thirteen Orphans are complete despite not being four sets and a pair (3.2)
Turn Order
- East begins and play proceeds counter-clockwise. East does not draw on their first turn, having started with fourteen tiles (3.3)
- Touching the wall to draw removes a player's right to call the previous discard (3.3)
Riichi
- A player with a concealed tenpai hand may declare riichi in three steps: clearly call "riichi", discard a tile rotated sideways, and place a 1,000-point stick as the riichi bet (3.3.10)
- Riichi may be declared only if at least one tile remains in the wall (3.3.10)
- After declaring, drawn tiles must not touch the hand — they are placed apart or discarded immediately (3.3.10)
- A riichi declarer who wins reveals the tiles beneath the dora indicators as ura dora, usable only by players who declared riichi (3.3.10)
- The declarer recovers their bet by winning; otherwise the winner collects it (3.3.10)
Declaring a Win
- Tsumo — winning on the tile just drawn, by clearly calling "tsumo". A furiten player may still call tsumo (3.3.11)
- Ron — winning on the most recently discarded tile, by clearly calling "ron", unless furiten (3.3.12)
- Robbing a quad — the tile added to an extended quad may be claimed for a win with "ron", treated as a win by discard, with the quad declarer paying (3.3.13)
- A player is furiten if they have discarded any tile they are waiting on, and may not then win by discard (3.3.9)
- Declaring a win by self-draw after discarding a tile is invalid (6.8)
- "Mahjong" is not a valid win declaration under the 2025 rules (6.5.3)
5. Scoring & Winning
Valuing a Hand
- All players are responsible for each hand being scored correctly and to the maximum; each player counts their own han and minipoints and others must correct mistakes (4.1)
- Count han first — the yaku (at least one) plus dora, kan dora, and ura dora. Ura dora count only for a riichi hand, and a tile marked by several indicators counts several times (4.1)
- Then count minipoints (fu) and round up to the next 10 — 32 becomes 40 (4.1)
- Seven Pairs is fixed at 25 minipoints with no rounding (4.1)
- At five or more han, minipoints are irrelevant (4.1)
- A pair of both the seat and round wind counts 2 minipoints, not 4 (4.1.1)
- Kiriage mangan: 4 han 30 minipoints and 3 han 60 minipoints are scored as mangan (4.1.2)
Payment
- Han and minipoints do not by themselves give the payment. The value of the hand is read from the scoring tables in section 8 of the official rules; this summary gives the procedure, not the tables (4.1, 4.1.3)
- Each counter on the table adds 100 points to a win by self-draw or 300 to a win by discard (4.1)
- The winner also collects riichi bets from players who did not win, including unclaimed bets from previous hands (4.1)
- With multiple winners the discarder settles with each winner individually, and each receives the full value of their hand including counters (4.1)
Ending the Game
- The game ends when the south round ends; the player with the most points wins, regardless of how many hands they won. Ties may occur (3.7)
- Riichi bets left on the table go to the winner, split on a tie with decimals rounded down (3.7)
- There is no bankruptcy rule (3.7, 4.1.4)
Winner Bonus (uma)
- Final scores are adjusted by uma: 1st +15,000, 2nd +5,000, 3rd -5,000, 4th -15,000 (3.7.1)
- Players tied for a position pool the relevant bonuses and split them evenly — two players tying for 1st share +20,000, taking +10,000 each (3.7.1)
6. Variants & House Rules
Riichi Compared with Other Mahjong
- Riichi is one of several mahjong rule families and is clearly distinct from the others, though all share the same core: build four sets and a pair from tiles
- Mahjong Competition Rules (MCR) is the other major competitive rule set. Its current text is the World Mahjong Organization's 2014 English edition, which supersedes the widely circulated 2006 "Green Book" that EMA still names as the reference for its MERS ranking tournaments — so a European MCR event may run under the older text. EMA runs MCR tournaments under its own MERS regulations, meaning the same association supervises play under both rule sets
- Japanese professional leagues each carry their own rule variations, and riichi rules exist in many versions differing in etiquette, scoring, and which variants are enabled
Common Options Not Used by EMA
- Red fives — widely used in Japan, where each red five gives one han. Not used in EMA riichi (1.3)
- Flower, season and joker tiles are set aside; they belong to other mahjong variants (1.3)
What Changed in 2025
- A delayed call for a triplet or quad no longer takes priority over a preceding call for a sequence (3.3.1)
- Riichi may now be declared with at least one tile left in the wall (3.3.10)
- Yaku are classified by their closed han value and lose value in open hands (4.2)
- An Etiquette chapter was added and the Errors and Penalties chapter expanded to list every error
Tournament Conventions
- Sessions may be time-limited; a hand is treated as beginning immediately after the previous one ends (3.1, 7.4)
- Organisers may supply an all-last sheet for tracking scores during the final hand (3.6)
- A chombo (major penalty) during the last hands of a timed session counts as one hand, to protect the schedule (3.4.6)