Riichi Mahjong · Closed 1 / open 1
Rinshan Kaihou (After a Kan) in Riichi Mahjong: Rules, Scoring and Odds
In riichi mahjong, Rinshan kaihou is worth 1 han: after a kan you draw a replacement tile from the dead wall (the "rinshan"), and if that tile completes your hand, you win with rinshan kaihou. It's a luck yaku — 1 han open or closed — and it's a yaku in its own right, so you don't need any other yaku to win.
On this page
The rules for Rinshan kaihou
- After any kan (closed kan, open kan from a discard, or added kan), win by tsumo on the replacement tile
- Tsumo only: winning by ron on someone's discard is never rinshan kaihou
- 1 han open or closed, no reduction for calling
- It's a yaku on its own: an open hand with no yaku can still win this way
- Once you discard after the replacement draw, the chance is gone — it's only that one tile
How Rinshan kaihou is scored
The yaku, han, fu and points below are computed live by the same scoring code the game uses.
Rinshan kaihou · Tsumo
| Menzen tsumo | 1 han |
| Rinshan kaihou | 1 han |
| Total | 2 han 60 fu · 1,000 / 2,000 points |
|---|
Non-dealer, East round, no dora, no honba.
Rinshan kaihou · Tsumo
| Rinshan kaihou | 1 han |
| Yakuhai: red dragon | 1 han |
| Total | 2 han 40 fu · 700 / 1,300 points |
|---|
Non-dealer, East round, no dora, no honba.
Rinshan kaihou is a tsumo win, so the 2 fu for tsumo still count. A closed kan keeps the hand closed, so menzen tsumo stacks with it. A kan is never a sequence, so pinfu is impossible.
What to know before you call kan
- Kan dora: every kan reveals one more dora indicator. As on Tenhou, a closed kan flips it at once; an open or added kan flips it after your next discard — so when you win on the replacement tile after an open kan, the new dora hasn't been revealed yet (some rulesets flip it immediately).
- The last tile moves up: each replacement draw shifts one tile from the end of the wall into the dead wall, so the live wall gets one shorter.
- A replacement tile is never haitei: even if it's the last draw of the hand, only rinshan kaihou counts, not haitei.
- The fourth kan: a hand allows four kans. If they belong to two or more players, the hand is aborted (suukaikan); if one player has all four, play goes on and that player is waiting on suukantsu.
- Kan after riichi: on this site only a closed kan of the tile you just drew, and only if it doesn't change your waits.
Rinshan kaihou odds
You need to call kan yourself and then draw exactly your winning tile, so it's rare. In 40,000 hands between four computers at normal level, rinshan kaihou was 0.13% of all wins — about once every 952 hands.
| Yaku | Share of wins |
|---|---|
| Ippatsu | 8.9% |
| Houtei raoyui | 0.77% |
| Haitei raoyue | 0.55% |
| Double riichi | 0.21% |
| Rinshan kaihou | 0.13% |
| Chankan | 0% |
Source: 40,000 computer hands on this site (all four at normal level), 33,226 wins. A win usually has several yaku, so the shares add up to more than 100%.
Rinshan kaihou in other mahjong styles
"Win on the kan replacement tile" exists everywhere, usually called "flower on the kong":
- Sichuan mahjong: 1 fan, plus "gang shang pao" for dealing in right after a kong (Sichuan Win After a Kong, Deal-in After a Kong)
- Chinese Official (Guobiao), "Out with Replacement Tile": 8 fan (Guobiao fan list)
- Taiwanese mahjong: 1 tai (Taiwanese mahjong tai list)
- Hong Kong mahjong: 1 fan (Hong Kong mahjong fan list)
FAQ
How many han is Rinshan kaihou?
Rinshan kaihou is 1 han, and 1 han when open. It's a yaku on its own, so no other yaku is needed.
Can you get Rinshan kaihou by ron?
No. It only counts for tsumo on the replacement tile after a kan. Winning on the tile someone adds to their pon is chankan.
Does Rinshan kaihou stack with Haitei?
No. Even if the replacement tile is the last draw, only rinshan kaihou counts.
What's the downside of calling kan?
Every kan adds a dora that everyone can use, and an open kan breaks your closed hand. To get a feel for when to kan, play a few hands of free online riichi mahjong against the computers.
Related yaku
Chankan Closed 1 / open 1
Ron the tile someone adds to their pon — 1 han. Rules, closed kans, scoring examples and how often it happens.
Sankantsu Closed 2 / open 2
Three kans by one player — 2 han, even open. Rules, big fu, common combos and the four-kan draw.
Haitei Closed 1 / open 1
Win by tsumo on the last tile of the wall — 1 han, open or closed. Rules, how the last tile moves, scoring and odds.
Try it at the table
Riichi Mahjong — Play Japanese Riichi Mahjong free in your browser against three AI opponents. Standard online rules with red fives, ippatsu and ura dora, a yaku guide, wait and furiten hints, and three AI levels. No sign-up.