Mahjong Furiten: The Complete Riichi Rule

Mahjong furiten is a Riichi rule that prevents a player from winning by ron. You become furiten when one of your current completing tiles appears in your own discards, or when you pass a discard that completes a valid hand. Furiten blocks every ron tile in the wait, but you may still win by tsumo.

The 3 forms of furiten

Mahjong Furiten: The Complete Riichi Rule: Form, Trigger, When it ends

Form	Trigger	When it ends
Discard furiten	Any current wait is in your own discard pool	When changing the hand removes that tile from the wait
Temporary furiten	You pass a discard that completes your valid hand	On your next draw or legal call
Riichi furiten	You pass a completing tile after declaring riichi	At the end of the hand

This guide follows World Riichi Championship Rules 2025. Some apps explain the rule with shorter labels, but the whole-wait effect is the essential point.

Discard furiten checks the complete wait

Imagine your hand can complete with either 3 Bamboo or 6 Bamboo. You discarded 3 Bamboo earlier. An opponent now discards 6 Bamboo.

You cannot declare ron. The 3 in your discard pool makes the entire 3–6 wait furiten. It does not matter that another player supplied the 6 or that you never discarded a 6.

This rule prevents a player from rejecting a tile and later taking an equivalent completing chance from someone else. It also makes every visible discard a record of responsibility.

Check furiten from the current hand shape, not from the shape you remember two turns ago. If you draw and discard so the hand now waits only on a tile absent from your pool, discard furiten can disappear. After riichi, your hand is locked, so you cannot redesign the wait that way.

A wait can cause furiten without a yaku

WRC defines furiten using a tile that forms a valid structure, even if that completed structure would have no yaku. This surprises players who check only the tile they intend to win on.

Suppose one side of a multiple wait creates a complete but yakuless hand, while another side adds a yaku. If the yakuless completing tile is in your discards, it can still make the whole wait furiten. A hand calculator that shows only scoring wins may hide this trap.

Separate two questions:

1. Which tiles complete a valid hand shape?
2. Which of those completed shapes have a yaku and can score?

Furiten uses the first set. A legal ron needs both a non-furiten state and at least one yaku.

Temporary furiten after passing ron

You become temporarily furiten when an opponent discards a tile that completes your valid hand and you do not call ron. Your reason does not matter. You may be waiting for a higher-value discard, avoiding a particular payer, or simply miss the tile.

Under WRC rules, temporary furiten lasts until your next draw or call. Another player’s pon, chii, kan, riichi declaration, or discard does not clear it. Once your own next turn begins by drawing, the temporary state ends; you must still check your discard pool for ordinary furiten.

Strategically passing ron is therefore possible before riichi, but it creates a window in which another opponent may discard your preferred tile and remain safe from your ron.

Riichi furiten lasts for the hand

After declaring riichi, passing any tile that completes your valid hand creates Riichi furiten. Because the hand is locked, the state lasts until that hand ends. You cannot ron a later copy from another player.

This includes deliberately declining a low-value win and accidentally missing the call. Online clients often enforce the state automatically; at a physical table, you must track it yourself.

Declaring riichi while already furiten is legal under WRC rules. That declaration does not restore ron. You are committing to a tsumo-only win unless the hand was not actually furiten.

What furiten does and does not block

Furiten blocks winning by ron, including winning by robbing a kan. It applies to every tile that completes the current valid shape.

You may still:

• win by self-draw and declare tsumo;
• draw and discard normally;
• call tiles to form groups when otherwise legal;
• declare a legal kan;
• change an undeclared hand to alter its waits; and
• declare riichi while furiten under WRC rules.

Furiten is not a dead-hand penalty. It changes the allowed win method, not your right to continue playing.

A reliable check before riichi

Use this sequence before placing the 1,000-point stick:

1. List every tile that completes the 13-tile hand.
2. Compare that full list with your own discard pool.
3. Include structurally complete tiles even when one result lacks yaku.
4. Check whether all physical copies are visible; an impossible wait can still be tenpai under WRC if the tile identity exists, but it cannot actually be drawn.
5. Decide whether a tsumo-only riichi is worth the deposit and locked hand.

Why furiten improves defensive play

Furiten makes a player’s own discards informative. If a tile is confirmed among an opponent’s waits and also appears in that opponent’s discard pool, that player cannot ron it while the wait remains unchanged.

Real defense is more complex because hands can change, multiple opponents matter, and temporary furiten is not always visible. Do not treat every tile near a discard as safe. Learn genbutsu, suji, wall evidence, and push-fold judgment separately in the Mahjong defense guide.

The shortest correct memory aid is: your discard or passed win can block ron on the whole wait; tsumo remains legal. Check all waits, not just the tile you hope to see.