Chiitoitsu: 2-Han Riichi Yaku With Example Hand

Overview

Chiitoitsu, seven pairs, is a special closed yaku worth 2 han that breaks the usual four-melds-and-a-pair structure: it is made of seven distinct pairs, each a different tile. It must be concealed, since pairs cannot be called, and it is always scored at a fixed 25 fu, giving it a distinctive payout. Most rule sets require the seven pairs to be genuinely different tiles, so four of a kind cannot count as two pairs. Chiitoitsu always finishes on a tanki (single-tile) wait completing the final pair, and it combines well with tanyao, honitsu, and especially riichi, where its tanki wait can be aimed at a safe or likely tile. It is a useful escape route when a hand holds many pairs but few good sequence or triplet shapes. Skilled players weigh chiitoitsu against a standard hand based on which reaches a stronger wait faster.

Conditions

The hand must consist of exactly seven pairs (14 tiles total, forming 7 pairs of 2 identical tiles each)
All seven pairs must be different; four of the same tile does not count as two pairs for chiitoitsu
The hand must be fully concealed (closed only); you cannot call pon, chi, or kan
Always scored as 25 fu with a flat 2 han, regardless of tile composition
Cannot combine with iipeiko or ryanpeikou since those require sequence interpretation

Strategy Tips

When your starting hand has four or five pairs, chiitoitsu becomes a realistic target. Count your pairs at the start and decide early whether to pursue this path.
Chiitoitsu tenpai is always a single tile wait (tanki), which can be hard to read for opponents. Use this to your advantage by waiting on a tile that appears safe or has few discards.
This hand pairs naturally with tanyao (all simples pairs), honitsu (one suit plus honors), or honroutou (all terminals and honors) for significant bonus han.