American Mahjong Rules: Official NMJL Rules Explained
American Mahjong follows rules set by the National Mah Jongg League (NMJL). The game uses 152 tiles and an annual card listing valid winning hands. Four players draw and discard tiles, trying to complete a hand that matches a pattern on the card.
Calling Rules
Players can call discards for Pungs (3 identical tiles), Kongs (4 identical), Quints (5 identical), or to win (Mah Jongg). Mah Jongg calls take priority over all others. You cannot call a tile for a pair except to win.
Joker Rules
Jokers are wild tiles that substitute for any tile in groups of 3 or more. They cannot be used in pairs or singles. Exposed Jokers can be exchanged by any player who holds the natural tile. See our deeper Joker rules guide for exchanges and edge cases.
Dead Hands
A hand is declared dead if a player has the wrong number of tiles, makes an invalid exposure, or incorrectly declares Mah Jongg. Dead hand players continue to play but cannot win.
Going deeper
- Joker rules and strategy: full Joker rulebook
- Scoring and payment math: point values and worked examples
- Three-player rules: adapting the game when you only have three players
- The Charleston: the tile-passing ritual
- Strategy guide: hand selection and defensive play