Kuitan - Open Tanyao Rule Allowing Called Hands

What is Kuitan?

Kuitan (open tanyao) is a rule where Tanyao can be completed even with called tiles. “Kui” means eating/calling and “tan” refers to Tanyao. Also written as 喰い断 or 食い断.

Originally Tanyao required a closed hand, but under kuitan rules, pon and chi are allowed while still counting as 1 han. Modern rules commonly use “kuitan ari” (allowed), making it beginner-friendly.

Rule Comparison

Rule	Tanyao Condition	Han	Difficulty
Kuitan ari	Calling OK	1 han	Easy
Kuitan nashi	Closed only	1 han	Hard

Requirements (Kuitan Ari)

Condition	Detail	Example
Simples only	2-8 number tiles	No 1,9,honors
Calling OK	Pon/Chi allowed	Open hand valid
4 melds + pair	Standard form	No special shapes

Examples

With Calls

Chi: 234m (sideways)
Hand: 456p 678s 345s 55p
→ All simples, kuitan valid, 1 han

Comparison

Closed: All in hand
234m 456p 678s 345s 55p
→ Tanyao 1 han

Open (kuitan):
[234m] chi 456p 678s 345s 55p
→ Tanyao 1 han (kuitan ari rules)

Where Kuitan is Used

Location	Kuitan	Reason
Most parlors	Ari	Standard rule
Competitive mahjong	Ari	Most leagues adopt
Online mahjong	Ari	Default setting
Some regions	Nashi	Traditional rules

Pros and Cons

Kuitan Ari Benefits

Beginner-friendly
- Easy to win
- Clear rules
Faster games
- Active calling
- Speed-focused
More tactics
- Aggressive play
- Flexible response

Kuitan Ari Drawbacks

Closed hand value drops
Harder to defend
More luck factor

Practical Kuitan Play

When to Aim for Kuitan

Mostly simples in hand
- Many 2-8 tiles
- Few terminals/honors
Speed priority
- Want to win fast
- Points over speed
Defensive reasons
- Stop opponents
- Avoid folding

Calling Decisions

Situation	Decision	Reason
Good shape complete	Call actively	Near tenpai
Many dora	Careful	Aim for closed mangan
Opponents look strong	Call early	Speed priority
Need points	Stay closed	Higher scoring

Kuitan Nashi Rules

Where Used

Some traditional parlors
Regional rules
Older rule sets

Adaptation

Stay closed
- No calling
- Tanyao closed only
Target other yaku
- Aim for yakuhai
- Sanshoku, ittsu, etc.
Value over speed
- Higher closed scores
- Riichi also in view

Ariari

Kuitan ari + Atozuke ari:

Most common rules
Beginner-friendly
Fast-paced

Arinashi

Kuitan ari + Atozuke nashi:

Fairly common
Good balance
Complete-first required

Nashinashi

Kuitan nashi + Atozuke nashi:

Traditional rules
High difficulty
Closed-focused

Strategy Points

Early Hand Assessment

Good kuitan starting hands:

9+ simples
Few terminals/honors
Dora is a simple

Abandon kuitan:

Many terminals/honors
Yakuhai pairs
Flush potential

Mid-Game Building

Call actively
- When shape is ready
- Speed priority
Cut terminals/honors
- Process early
- Save as safe tiles
Stay flexible
- Situational
- Closed option too

Common Mistakes

Not confirming rules
- Always check before play
- Kuitan nashi exists
Chiitoitsu confusion
- Chiitoitsu can’t call
- Kuitan is 4 melds + pair
Atozuke confusion
- Kuitan: Can call for tanyao
- Atozuke: Can call without yaku
Pinfu combination
- Calling breaks pinfu
- Pinfu is closed only

Tanyao: All simples yaku
Ariari: Kuitan + atozuke allowed
Nashinashi: Neither allowed
Kanzen-sakizuke: Complete-first rules
Menzen: Closed hand state

Summary

Kuitan allows Tanyao completion with called tiles. Modern rules commonly allow kuitan, recognizing pon/chi while still granting 1 han. It’s beginner-friendly with fast-paced gameplay, used in most parlors and competitive mahjong. Always confirm “kuitan ari?” before playing, and when allowed, actively collect simples with calls. Tanyao is the most basic yaku, so use kuitan rules to gain winning experience.