Best for Riichi players who want a quicker, higher-variance game – bigger hands, constant pon calls, and the dama-over-riichi tension that tsumo-loss creates.
Sanma trims the four-player set in one place: the characters suit is cut down to its two terminals. Everything else – the full dots and bamboo suits, all four winds, all three dragons – is the standard Riichi set, four of each kind. There are still no flowers, seasons, or bonus tiles. The total drops from 136 to 108.
The goal. A winning hand is 14 tiles: four sets, plus one pair – or one of two special shapes. Between turns you hold 13; the 14th is the tile that completes your hand, whether you draw it yourself or claim it from a discard.
Any combination of these counts. Your hand does not need one of each.
Two special shapes skip this four-sets-plus-pair structure entirely: Seven Pairs (seven different pairs, no sets at all) and Thirteen Orphans (one of every terminal and honour, plus a duplicate of any one) – both still buildable in Sanma, since the character terminals remain. Both are defined fully as scoring patterns in Section 07.
To win, your hand must pass both checks
A hand can pass Shape and still fail Value: a structurally complete hand with no yaku is not a legal win yet, even one tile from finishing. Keep improving it, or declare riichi and wait – full rules in Section 06.
A reaction window opens on each discard and closes the moment the next player draws. Only the most recently discarded tile can be claimed, and you cannot claim your own discard.
This catalog is your hand's Value, itemized. Every pattern below is a yaku: a named hand pattern worth a set number of han. Clearing the win gate means qualifying for at least one yaku on this list – keep this section open while you decide what your hand is trying to become.
This is the one genuinely new system in Sanma. The North tile is no longer a seat wind – it is a bonus dora you harvest. On English clients it shows as kita; the Japanese term is pei nuki (北抜き).
On your turn, after drawing, if you hold a North tile you may declare "kita," lay it face-up beside your hand like a small open meld, and immediately draw a replacement tile from the dead wall. The North you set aside is worth +1 dora. Then continue your turn and discard as normal. You may pull as many Norths as you draw, one per declaration.
At the deal, one tile on the dead wall is flipped face-up as the dora indicator. The indicator does not score itself – it points to the tile that does: the next tile in sequence after it. Every dora tile in your final hand is worth +1 han, on top of anything else the hand already earns.
Sanma uses a running bank, the same as Riichi. Each player starts with 35,000 points (higher than four-player Riichi's 30,000, since there's one fewer player to take from). The valuation engine is identical to four-player Riichi – same han, same fu, same base-value formula and limit names. The only twist is in who pays and how much on a self-draw.
Han is a running tally: every yaku your hand qualifies for (Section 07), at its listed value, plus +1 for every dora tile (Section 09). An open hand loses a han on any yaku marked ↓. Once you have the total: 1–4 han needs a fu count below; 5+ han skips fu entirely and reads straight off the limit tiers.
Han, fu, and base value are all identical to four-player Riichi. What changes is the self-draw: with only two opponents, a tsumo settles for less than the same hand won on a discard. This is the tsumo-loss convention, the default on Tenhou.
Take a non-dealer mangan (base 2,000). The ron and tsumo totals are no longer equal:
Same hand, same 8,000 ron value as four-player – but the self-draw brings in 6,000 because the fourth player's 2,000 share doesn't exist to collect. In four-player Riichi this same mangan tsumo would total 8,000 (2,000 + 2,000 + 4,000).
If the live wall runs out with no winner, players reveal whether they are tenpai (ready) or noten, declaring in turn from East. Sanma uses a smaller penalty pool than four-player Riichi: 2,000 points, not 3,000. The noten side pays the tenpai side:
Riichi deposits stay on the table for the next winner. A tenpai player may choose to declare noten and hide, except after declaring riichi, which forces a tenpai reveal. Some local tables instead use a 3,000-point pool – agree which before you start.
Players rank by final points. The break-even point is the 35,000 each player started with. Most Sanma applies a placement bonus (uma) to the three finishers, but the exact figures vary by platform and table – a common online spread is roughly +15 / 0 / −15 for first, second, and third, sometimes with a starting-to-target points adjustment (oka).
Yes, identically – four sequences, a valueless pair (guest wind allowed, dragons and valued winds not), fully concealed, won on a two-sided wait. Nothing about Sanma's tile set or player count changes this pattern.
No – only one. The win goes to whichever eligible player sits nearest counterclockwise after the discarder (the “head-bump”); how fast anyone calls doesn't matter. There's only ever one winner per hand. Same rule as Riichi.
Partly. Swap-calling (kuikae) still bans claiming a tile and then immediately discarding that exact same tile back. But the other half of the Riichi rule – claiming a tile for a sequence and then discarding the tile from the other end of that run – can't come up at all in Sanma, since chii doesn't exist here in the first place.
No. Robbing the kan (chankan) only applies to a kan made by adding a tile to an already-exposed pon. A concealed kan is placed all at once, straight from your hand, so there's no equivalent moment to rob – an ankan is always safe from chankan.
Not by default, same as Riichi – it's an optional house addition, not part of the standard ruleset. If your table adds them, Sanma only carries two, not three: one red 5-pin and one red 5-sou, since the characters suit has no 5 left to make red.
Yes, and it doubles. The wind dora order runs East → South → West → North → East, so a West indicator points to North as that hand's regular dora. When that happens, every North tile you've pulled aside for kita is worth its usual +1 kita han plus +1 more as an ordinary dora hit – 2 han per kita instead of 1. Any other indicator, and kita stays a flat +1. Watch the indicator before you commit to pulling North.
Same logic as Riichi – East stays after winning, with a honba added, and stays after a draw only if East is tenpai. The rotation itself is just faster with three seats: when the deal does pass, South becomes the new East and everyone shifts one place counterclockwise.
Same tenpai/noten reveal as Riichi, but with smaller numbers – Sanma uses a 2,000-point pool by default instead of 3,000 (some tables use 3,000 instead; agree beforehand). With only two opponents, there are only two possible splits: one noten player pays 1,000 to each of the two tenpai players, or two noten players each pay 1,000 to the lone tenpai player.
This is a guide to Japanese Sanma Mahjong, built from community-sourced Sanma reference documents (Sanma_Reference.md, Sanma_Difference.docx), read as a delta against the WRC 2025 Riichi rules.
Played it differently at your table, or think there's a more common way to run a rule? Let us know – genuinely appreciated, and repeated feedback can shape a revision.
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