What is Penchan Machi? Edge Wait Pattern and Tactics Explained for Beginners

What is Penchan Machi (Edge Wait)?

Penchan machi (辺張待ち) is a tenpai pattern waiting for with , or waiting for with . It refers to forms at the edges of numbered tiles (1-2 or 8-9), waiting for the outside tile.

This is one of the most inefficient waits and representative of “bad waits” (gukei). Also called “pen3” (pen-san) or “pen7” (pen-chi).

Detailed Explanation of Penchan Machi

Types of Penchan Machi

Penchan Machi Characteristics

Usage Examples

Real Game Situations

Example 1: Tenpai Declaration

"Tenpai on pen3... tough"
":8m::9m: pen7 wait, this is harsh"

Example 2: Riichi Judgment

"Penchan but 3 dora, so riichi"
"Cheap penchan, definitely dama"

Example 3: Hand Building Regret

"Why did I accept into penchan..."
"Keeping penchan was a mistake"

Problems with Penchan Machi

Why is Penchan the Worst?

Specific Problems

1. is used in , ,
2. is used in , ,
3. and are easily discarded early

Related Terms

• Ryanmen Machi: Most efficient wait
• Kanchan Machi: Middle wait, bad form
• Gukei: General term for bad waits
• Penchan Taatsu: , forms
• Pen3/Pen7: Colloquial for penchan

Common Mistakes and Points to Note

Points Beginners Often Mistake

1. or are not penchan

   • These are ryanmen machi
   • Only and are penchan

2. Keeping penchan too long

   • Should handle early
   • Don’t drag to the end

3. Missing all 4 visible

   • All four or already visible
   • Effectively formal tenpai

4. Expecting change too much

   • Drawing with still becomes kanchan
   • Not fundamental solution

Countermeasures for Penchan Machi

Early Game: Handle Early

If :1m::2m: in starting hand
→ Discard as unnecessary early

Mid Game: Prioritize Other Waits

If you have :1m::2m: and :3p::5p:
→ Keep :3p::5p: (kanchan), discard :1m::2m:

Late Game: Situational Judgment

Riichi Judgment on Penchan Machi

When Riichi Has Value

1. Mangan or higher hand
2. Dealer’s consecutive wins at stake
3. Last round conditional battle
4. Many dora or yaku

When Dama is Better

1. About 1000 point cheap hand
2. Still early turns
3. Opponent has riichi
4. Defense-focused situation

Special Use of Penchan Machi

Defensive Penchan Machi

Against opponent's riichi
→ Penchan wait with safe tiles :8m::9m:

Can defend while aiming for win

Penchan in Junchan

Junchan requires :1m::2m:, :8m::9m:
→ Penchan has value

Penchan Machi Statistics

Win Rate

• Ryanmen machi: About 40%
• Kanchan machi: About 20%
• Penchan machi: About 18%
• Tanki machi: About 15%

Penchan machi is statistically one of the hardest waits to win with.

Conclusion

Penchan machi, waiting for with or with , is the most inefficient wait pattern. With few acceptance tiles and little expectation of good wait changes, beginners should be careful not to create penchan taatsu from the starting hand. However, judgment to gamble even on penchan is necessary with high points or special situations. Learn the proper relationship with penchan machi and aim for more efficient mahjong.