Menzen Tsumo - Winning by Self-Draw Without Calling

What is Menzen Tsumo?

Menzen Tsumo is a 1 han yaku for winning by self-draw while keeping a closed hand (no pon, chi, or open kan). Also called just “tsumo” or “mentsumo,” it’s one of the most basic yaku.

By staying closed (no calls) and winning on your own draw, you earn 1 han. Tsumo wins collect from all players, often totaling more than ron wins.

Requirements

Condition	Detail	Notes
Closed hand	No pon/chi/open kan	Ankan OK
Tsumo win	Win on self-draw	Not ron
No other yaku needed	This alone is 1 han	Saves yakuless hands

Closed Definition

OK (stays closed):
- No calls made
- Ankan (4 self-tiles)

NG (breaks closed):
- Pon
- Chi
- Open kan (opponent's tile)

Examples

Basic Form

Hand: 123m 456p 789s 22E 55s
Tsumo tile: 5s (completes triplet)
→ Closed tsumo win, Menzen Tsumo valid

Yakuless Tsumo

Hand: 234m 567p 345s 999s 88p
Tsumo: 8p
→ No other yaku, but tsumo makes 1 han

Scoring Comparison

Non-dealer 2 han (40 fu):

Win Type	Dealer Pays	Non-Dealer Pays	Total
Tsumo	1,300	700 × 2	2,700
Ron	-	-	2,600

*Tsumo wins 100 more

Tsumo Loss/Gain

Tsumo loss:

Low points (30 fu 1 han, etc.)
Ron sometimes better

Tsumo gain:

High points (mangan+)
Dealer tsumo
Multiple yaku

Strategic Use

When to Aim for Tsumo

Few yaku
- No other yaku
- Tsumo adds 1 han
As dealer
- Dealer tsumo profitable
- Collects more from everyone
After riichi
- Riichi + tsumo = 2 han
- Ippatsu/dora combinations

When to Choose Ron

Cheap hand
Want to win quickly
Direct hit on specific player
Want to knock out dealer

Common Combinations

Yaku	Combination	Total
Riichi	Closed + riichi	2 han
Pinfu	Closed + good shape	2 han
Tanyao	All simples	2 han
Iipeikou	Identical sequences	2 han
Rinshan	Win on kan draw	2 han

Combination Example

Riichi Tsumo Tanyao Dora 1:

Hand: 234m 456p 567s 345s 55p
After riichi, tsumo 5p
→ 4 han (3,900 or 7,700)

Strategic Value

Why Stay Closed

Tsumo adds 1 han
- Even yakuless can win
- Score boost
Riichi possibility
- Riichi is closed-only
- Ura-dora chance
Pinfu possibility
- Pinfu is closed-only
- Becomes 2 han

When to Call

High yaku guaranteed
Speed priority
Defense win needed
Many dora present

Occurrence Rate

Statistics:
Closed tsumo wins: ~40%
Tsumo-only wins: ~5%
Riichi + tsumo: ~30%

Common Mistakes

Ron confusion
- Ron doesn’t work
- Tsumo only
Called hand tsumo
- Invalid after pon/chi
- Closed required
Ankan handling
- Ankan doesn’t break closed
- Rinshan combination possible
Yakuless misunderstanding
- No other yaku needed
- Tsumo itself is 1 han

Psychology of Tsumo

Effects on Opponents

Everyone pays
- Not just 1 person
- Points distributed
Riichi pressure
- Worry about being tsumoed
- Suppresses attacks
Renchan expectation
- Dealer tsumo
- Round continues

Menzen: Closed hand state
Tsumo: Self-drawing
Hora: Completing hand
Riichi: Common combination
Pinfu: Common combination

Summary

Menzen Tsumo is a 1 han yaku for winning by self-draw while closed. Even without other yaku, staying closed and tsumoing grants 1 han. Tsumo wins collect from everyone, often totaling more than ron. Beginners should remember “closed + tsumo = 1 han” and keep trying for tsumo even without obvious yaku. Balance between closed play and calling while pursuing riichi and pinfu combinations.