Building the four walls is the first job at an American mahjong table, and once you know the pattern it takes only a couple of minutes. Each of the four players builds one wall that is 19 stacks long and two tiles high, with every tile face down, and together the four walls hold the full set of 152 tiles. This guide shows you how to build mahjong walls step by step, why those numbers always add up, and what to do when a wall comes up short.
Key takeaways
- Every player builds one wall: 19 stacks long, 2 tiles high, tiles face down.
- 19 stacks x 2 tiles = 38 tiles per wall, and 4 walls x 38 = 152 tiles, the size of a full American set.
- Mix all the tiles face down before building so nobody can see or guess what is where.
- Spare blank tiles, if your set has them, are not part of the 152 and stay in the box.
- Counting stacks out loud at the end is the quickest way to catch a missing or extra tile.
Before you build
You need four players, a flat table with some elbow room and the full set of tiles. Many players like to lay a soft mat on the table first, because it quiets the clicking and stops tiles from sliding around. A mat is a comfort rather than a requirement. If you have racks, set one in front of each player now: the wall is built in front of the rack, against its pusher, which later slides the wall toward the centre. Without racks, build the walls directly on the table.
Take out anything that is not a playing tile
A complete American set has 152 playing tiles: 36 dots, 36 bams, 36 craks, 16 winds, 12 dragons, 8 flowers and 8 jokers. Some retail sets also include a few spare tiles, such as blanks, so the number printed on a box can be higher than 152. Those extras are not part of play. Put them aside before you start mixing so a spare never ends up in a wall.
If you are still choosing a set, our guide to how many tiles are in an American mahjong set explains the count in detail.
Building the walls, step by step
- Tip the tiles out face down. Spill every playing tile onto the middle of the table with the faces turned toward the tabletop.
- Mix them thoroughly. Sweep the tiles around with both hands for a good few seconds. Many groups call this washing the tiles. The goal is that tiles that were neighbors in the box are no longer neighbors.
- Each player pulls tiles toward their own side. Everyone works at once, so the whole job takes a minute or two.
- Stack them two high. Line up tiles in a row, face down, and set a second tile on top of each one. You are aiming for 19 stacks.
- Square up the ends. Tap the ends of your wall so every stack lines up. A ragged wall is hard to count and easy to knock over.
- Count your stacks. Touch each stack as you count to 19. If everyone agrees, each player slides their wall toward the centre of the table, usually with the rack's pusher, so the four walls form a square.
The next step is deciding who sits in the dealer seat and where the wall opens. That is covered in our guide to who deals first and rolling for East.
Why 19 stacks, two tiles high
The numbers are a built-in check. One wall holds 19 x 2 = 38 tiles, and four players build four walls, so 4 x 38 = 152. That matches the playing set exactly. If a wall finishes a stack short, or a tile is left over in your hand, then a tile is missing or an extra has slipped in.
| What you are counting | Number |
|---|---|
| Stacks in one wall | 19 |
| Tiles in each stack | 2 |
| Tiles in one wall | 38 |
| Walls (one per player) | 4 |
| Tiles in all four walls | 152 |
The 152 itself breaks down as 108 suit tiles (dots, bams and craks, nine numbers, four of each), 16 winds, 12 dragons, 8 flowers and 8 jokers: 108 + 16 + 12 + 8 + 8 = 152. Notice that the jokers are part of the 152, not extra tiles added on top.
Building two high is practical as well as tidy. A double row is steadier than a single line when the walls are pushed together, and it is easier to draw from once play begins.
Worked example: a wall that comes up short
Imagine a made-up table of four players. Dana counts her wall and gets 18 stacks instead of 19. That is 36 tiles, two short of a full wall. Before anyone worries, work through it in order.
- Recount Dana's wall. Count stacks, not tiles, and touch each one. Miscounts happen when a stack is nudged out of line.
- Check the other three walls. If Ravi's wall has a single tile sitting at one end, or a stack that is three high, that is probably where the missing stack went.
- Look around the table. Check the table edge, the floor, the box and any pile of spares you set aside earlier. Tiles slip under mats more often than you would expect.
- Still stuck? Count the whole set once more. If the total is really 150, two tiles are missing and you should find them before play starts, because a hand cannot be completed correctly with the wrong tiles in the wall.
The same logic works in reverse. If one wall has 19 stacks and there are leftover tiles on the table, a spare has probably wandered in or a stack was built one tile high. Fixing it now costs a minute. Finding it halfway through a hand costs a lot more.
Common mistakes
- Tiles left face up. Turn them over before anyone studies them. Nobody should know what is in the walls.
- Mixing too briefly. A quick shuffle can leave suits clumped together. Give the tiles a proper wash.
- Uneven walls. If one wall is longer or shorter than the rest, rebuild it instead of trusting the count later.
- Counting tiles instead of stacks. Counting 38 tiles one by one is slow and error-prone. Count 19 stacks of two.
- Building one tile high. A single row of 38 stretches across the table and is harder to push to the centre.
- Spares in the mix. Blank or extra tiles do not belong in the walls. Remove them first.
Sets that include spares are one more reason to know the playing count. A SOLMAY set has exactly 152 tiles, so there is nothing to remove.
About our sets. A SOLMAY American mahjong set has exactly 152 tiles (36 dots, 36 bams, 36 craks, 16 winds, 12 dragons, 8 flowers and 8 matching jokers), each 35 x 25 x 11 mm, with original artwork UV-printed on glossy pearlescent acrylic. Sets are printed to order in Vietnam. Racks, pushers, mats, bags and the yearly card are not included. See the mahjong sets.
Quick reference and a practice exercise
| Step | What to do |
|---|---|
| 1 | Remove spare or blank tiles, if your set has any |
| 2 | Tip all 152 tiles face down and mix them |
| 3 | Each player builds a wall: 19 stacks, 2 high |
| 4 | Square up the ends and count the stacks aloud |
| 5 | Push the walls together into a square |
Try it at your next game
As each wall is finished, have its builder call out the stack count: "nineteen." Five seconds of counting at the start can head off a long debate about a missing tile later. If you play at a table for the first time with new friends, ask who has the habit of mixing the longest and let that person set the pace.
For the official side of the game, the National Mah Jongg League publishes the yearly card that American players use. The card lists the hands themselves, not the table setup, so your group's habits fill in the rest.
Frequently asked questions
How many tiles are in each mahjong wall?
Each wall has 38 tiles, arranged as 19 stacks that are two tiles high. With four players building one wall each, the total is 152 tiles, which is the full American mahjong set including the 8 jokers.
Do you have to mix the tiles before building the walls?
Yes, in practice you do. The tiles should be face down and thoroughly mixed so nobody knows what is in the walls. Most groups simply swirl the tiles around the table with both hands before anyone starts building.
What if my set has more than 152 tiles?
Some sets are sold with spare tiles, such as blanks or extra jokers, so the box can show a number like 160. Only 152 tiles are used in play. Set the extras aside before you build so they do not end up in a wall.
What happens if one wall has 18 stacks?
Recount first, then check the other walls for a stray single tile or an oversized stack. Look under the mat, on the floor and in the box. A wall that is truly short means a tile is missing, and it is better to find it before the deal.
Can you build a wall with tiles face up?
You should not. Walls are built face down so that nobody can see what is coming. If tiles were turned face up by accident, flip them and mix again before building.
Do all four players build their walls at the same time?
Most groups do, which keeps setup quick. Each person works in front of their own seat. Just agree to count together at the end so every wall is checked.
Keep reading
- Who deals first? Rolling for East
- 13 and 14: how many tiles everyone starts with
- How many tiles are in an American mahjong set?
- What you need to play American mahjong
- A 60-second way to sort your rack
These guides follow the way American mahjong is commonly played with the National Mah Jongg League card. Groups sometimes add house rules, so agree on yours before the first hand, and always use the current year's official card. SOLMAY is not affiliated with the NMJL.
