A season is a unit of time in Redwall. It is the most common unit used to refer to a period of time spanning several months. There are four seasons: spring, summer, autumn, and winter. According to the introduction of the Tenth Anniversary edition of Redwall, four consecutive seasons are equivalent to one human year, but the term "year" is never used in Redwall (with the exception of the very first book, Redwall) and Mossflower. Individual season names are sometimes used in place of years to imply years; for example, "four summers ago" means the same thing as "four years ago."

Seasons often mark milestone events in the history of Redwall and are named on Nameday. They are celebrated by a feast.

Documented Seasons in Redwall Abbey