Professional sumo holds six official tournaments (honbasho) a year, each lasting 15 days, in odd-numbered months, rotating among four cities:
Sumo has six divisions — Makuuchi, Juryo, Makushita, Sandanme, Jonidan, and Jonokuchi. The top two (sekitori) wrestle 15 bouts per tournament; the lower four wrestle seven.
The highest rank. Yokozuna can never be demoted and are expected to retire if their performance declines. Promotion requires consecutive tournament victories (or equivalent) along with demonstrated dignity and grace.
The second-highest rank. Promotion typically requires around 33 wins over three consecutive tournaments at san'yaku level. An ozeki who posts a losing record is placed on probation (kadoban); a second consecutive losing record means demotion.
The third-highest rank. Sekiwake are strong contenders often on the path toward ozeki promotion. There must be at least one sekiwake on each side (East and West).
The fourth-highest rank and the entry point of the named ranks. Komusubi face the toughest schedule, regularly matched against yokozuna and ozeki.
The rank-and-file wrestlers of Makuuchi. They are numbered from 1 (highest) downward. Higher-numbered maegashira face lower-ranked opponents, while those near the top face san'yaku wrestlers regularly.
The banzuke is the official ranking list, redrawn before each tournament by the Japan Sumo Association. Every wrestler has a rank and a side — East or West — with East traditionally the more prestigious.
Rankings adjust after each tournament on win-loss record. A winning record (kachi-koshi) generally rises; a losing record (make-koshi) falls. The exact movement depends on the margin and on the wrestlers around the same rank.
At the end of each tournament, up to three special prizes may be awarded to Makuuchi wrestlers ranked below ozeki who post a winning record:
Awarded for an exceptional overall performance — typically for defeating one or more yokozuna or ozeki, or being a strong championship contender.
Awarded for exceptional determination and aggressive sumo throughout the tournament — often for impressive wins through sheer tenacity.
Awarded for superior technical skill — a wide variety of techniques, or especially refined belt work and throws.