Chow

A chow (called a shuntsu in Japanese and soeng in Cantonese) is a meld of three consecutive number tiles in the same suit, such as 4m-5m-6m or 6p-7p-8p. It is one of the two standard three-tile groups, the other being the pung. Because a sequence relies on numerical order, chows can only be built from the three suited families: characters/man (m), dots/pin (p), and bamboo/sou (s). Honor tiles, winds and dragons can never form a chow because they have no numeric sequence. A run also cannot wrap around, so 8s-9s-1s is illegal.

Chows can be concealed or claimed. You may call 'chi' to complete a chow, but only from the discard of the player immediately to your left (the one whose turn precedes yours), unlike a pung which can be claimed from anyone. This restriction is consistent across riichi, Chinese, and Hong Kong rules.

Scoring treats chows very differently across variants. In Japanese riichi, sequences are central to common yaku like pinfu (an all-chow hand with a non-value pair and a two-sided wait), iipeikou (two identical chows), and sanshoku doujun (the same sequence in all three suits). In Hong Kong and some Chinese styles, a hand may need to be 'all pungs' or 'all chows' to score certain bonuses, and a basic chow-heavy hand often earns little on its own. Sichuan bloody rules typically forbid claiming chows entirely.

For example, holding 4m-5m gives you a two-sided wait completed by either 3m or 6m; holding 4m-6m is a closed (kanchan) wait needing exactly 5m, which is narrower and, in riichi, blocks the pinfu yaku.