The company is the basic unit of military organization in the Kingdom of Valyria, associated with and also known as a banner. Companies are usually led by barons, which means a company is about the number of troops that can be housed in a fortress or larger sized settlement. Anyone leading a company is identified with the military rank of captain.

An important aspect of company organization is that they should be composed of multiple retinues which are led by the vassal knights of a baron. Because knights banneret are also capable of taking other knights as vassals, bannerets are also the leaders of their own companies.

When counts or viscounts take the field as the leaders of their county militia, they are also considered captains, and their troops a company.