American Mahjong Rules: The Complete Guide

The Basics

American Mahjong is a four-player tile game governed by the National Mah Jongg League (NMJL). The goal is simple: be the first player to collect a complete hand that matches one of the patterns on the current year’s NMJL card. Everything else — the dealing, the passing, the drawing and discarding — is just the path to get there.

If you’ve played other versions of Mahjong, American rules will feel both familiar and foreign. The bones are the same, but Jokers, the annual card, and the Charleston set the American game apart.

The Tiles

An American Mahjong set contains 166 tiles:

Craks (Characters) — tiles numbered 1 through 9, four of each (36 tiles)
Bams (Bamboo) — tiles numbered 1 through 9, four of each (36 tiles)
Dots (Circles) — tiles numbered 1 through 9, four of each (36 tiles)
Winds — North, East, South, West, four of each (16 tiles)
Dragons — Red, Green, White (Soap), four of each (12 tiles)
Flowers — eight flower tiles (8 tiles)
Jokers — eight joker tiles (8 tiles)
Blank tiles — for replacements if you lose one (not used in play)

If you’re coming from Chinese Mahjong, the big additions are the eight Jokers and the extra Flowers. These change the strategy considerably.

Setting Up

Building the Wall

Each player takes a section of face-down tiles and arranges them into a wall: two tiles high, typically 19 tiles long (some sets adjust this depending on tile count). Push the four walls together to form a hollow square in the center of the table.

Breaking the Wall

The designated East player (the first dealer) rolls two dice. The total determines where the wall is broken. Count that many stacks from the right end of East’s wall, then separate the wall at that point. Dealing begins from the break.

Dealing

Starting with East, each player takes four tiles at a time from the wall. Go around the table — East, South, West, North — four tiles each, three times. That gives everyone 12 tiles. Then each player takes one more tile, and East takes one additional tile (since East goes first).

Final count: East has 14 tiles. Everyone else has 13.

The Charleston

Before play begins, players exchange tiles through a structured passing sequence called the Charleston. This is unique to American Mahjong, and it’s one of the things that makes the game strategic from the very first moment.

First Charleston (Mandatory)

All four players must participate:

Right — pass 3 tiles to the player on your right
Across — pass 3 tiles to the player across from you
Left — pass 3 tiles to the player on your left

Second Charleston (Optional)

If all four players agree, a second round of passing begins in reverse order:

Left — pass 3 tiles to the player on your left
Across — pass 3 tiles to the player across from you
Right — pass 3 tiles to the player on your right

If any single player says no, the Second Charleston doesn’t happen.

Courtesy Pass

After the Charleston, the player across from you may offer to exchange tiles. You can swap zero, one, two, or three tiles. Both players must agree on the number.

If you don’t have three tiles worth giving away during a required pass, you can “blind pass” — include tiles you just received without incorporating them into your hand. Blind passes are only allowed on certain passes (not the very first pass of the First Charleston).

For a deeper look at strategy and timing, see our full article on the Charleston.

Gameplay

The Turn

Play moves counterclockwise, starting with East. On your turn:

Draw a tile from the wall (or claim a discard — more on that below)
Optionally exchange a natural tile for a Joker in another player’s exposure
Discard one tile face-up, announcing its name so all players can hear

That’s it. Draw, maybe swap a Joker, discard. Repeat around the table.

The NMJL Card

While you play, you’re working toward completing one of the hands listed on the NMJL card. The card is organized into categories — things like 2468, Consecutive Run, Winds and Dragons, Singles and Pairs — and each hand has a specific point value.

You need to have your physical card in front of you during the game. The hands change every year, so last year’s card won’t work. You can purchase one from nationalmahjonggleague.org.

If the card’s notation looks confusing at first, we have a guide on how to read the NMJL card.

Calling Tiles

When any player discards a tile you need, you may be able to claim it. This is called “calling.”

When You Can Call

To complete a pung (3 of a kind), kong (4 of a kind), quint (5 of a kind), or sextet (6 of a kind)
To win — you can call any discarded tile that completes your hand, including for a pair

When You Can’t Call

You cannot call a tile to form a pair unless it completes your Mahjong
You cannot call a tile for a single unless it wins
Calling for a sequence (like 1-2-3 in a row) is not part of American Mahjong — that’s a Chinese Mahjong rule

How Calling Works

When a tile you need is discarded, say “Call” (or the group name, like “three Bam”). You must immediately reveal the group by placing it face-up on your rack. These revealed tiles are called an exposure.

Priority

If two players want the same discarded tile, the player calling for Mahjong takes priority. Otherwise, the player calling for the largest group takes priority. If there’s still a tie, the player closest to the discarder (in turn order) wins the call.

Exposures

Once you call a tile and place a group on your rack, it’s exposed. Exposed tiles stay face-up for the rest of the round. Other players can see them, which gives them information about what hand you’re pursuing.

Some hands on the NMJL card are marked with a “C” for concealed. These hands cannot have any exposures — you must complete them entirely from the wall (except for the final winning tile, which may be a discard). Concealed hands are worth more points but are significantly harder to achieve.

Jokers

Jokers are the wildcard of American Mahjong. Here’s how they work:

A Joker can substitute for any tile in a group of three or more (pung, kong, quint, sextet)
Jokers cannot be used in pairs
Jokers cannot be used in Singles and Pairs hands
Jokers cannot be discarded (well, technically they can, but no one can pick them up — so it’s almost always a mistake)

Joker Exchange

If another player has an exposed group containing a Joker, you can swap it out. On your turn, after drawing a tile, place the natural tile that matches the group onto their exposure and take the Joker for yourself. You can do this before discarding.

This is one of the most satisfying plays in the game — and one of the things that makes American Mahjong tactically distinct.

Winning

A player wins by completing a hand that exactly matches one of the patterns on the NMJL card. When you complete your hand, call “Mahjong!” and reveal your tiles.

Self-Drawn vs. Discard

Self-drawn (from the wall): You pick the winning tile yourself. You collect from all three players.
From a discard: You call another player’s discarded tile to complete your hand. The player who discarded the winning tile pays double.

Scoring

Each hand on the NMJL card has a point value (typically 25 or 30 for common hands, 50+ for harder ones). The winner collects that amount from each losing player. The player who discarded the winning tile pays double their share.

If the game ends with no tiles left in the wall and no one has won, it’s a wall game — no one pays, and the deal passes to the next player.

Dead Hands

If you make an illegal exposure — for example, exposing the wrong tiles or calling incorrectly — your hand is declared dead. You must continue drawing and discarding for the rest of the round, but you cannot win. It’s a painful penalty, so double-check before you call.

House Rules

The NMJL publishes official rules, but many home groups add their own tweaks. Common house rules include minimum hand values, adjusted payment structures, or rules about the pace of play. If you’re joining a new group, always ask about table rules before the first hand.

Putting It All Together

American Mahjong has a lot of moving parts, but the core loop is simple: draw, discard, try to build your hand. The complexity — and the fun — comes from reading the card, reading the table, and making smart decisions about when to commit, when to pivot, and when to play it safe.

The best way to learn is to play. Mahj Parlour handles all the rules for you — dealing, the Charleston, tile validation, scoring — so you can focus on learning the strategy without worrying about getting a rule wrong. Practice against bots, then bring your friends to the table when you’re ready.

If you want to brush up on terminology first, our American Mahjong glossary covers every term you’ll hear at the table.