Embodiments of a method and system for listing categorization are disclosed. A category structure may be accessed. The category structure may include a plurality of categories for items. A set of training data may be accessed from a plurality of listings from at least one of supply data and/or demand data. The supply data may be generated from seller activity of a plurality of users in a networked system. The demand data may be generated from buyer activity of the plurality of users in the networked system. Each listing may include a category from the category structure. The set of training data may be provided to a categorization application for training. The categorization application may be capable of building listing statistics by applying a classifier to the set of training data and recommending a category from the category structure for a new listing by utilizing the listing statistics.