What premium service is used for individual or companies that have more mail each day than the largest box holds?

The premium service referred to for individuals or companies that have more mail than what the largest box can hold is caller service. This service is designed for customers who receive a high volume of mail and cannot fit it into the standard mailbox size. With caller service, mail is held at the post office, and customers are notified to come and collect their mail, ensuring that larger quantities of mail can be efficiently managed.

Other options do not serve this specific purpose. Priority Mail refers to a mailing option with expedited delivery times but does not specifically address the storage of large volumes of mail. Firm holdout is a service arrangement where mail is temporarily held for the recipient to pick up, but this is not tailored specifically for businesses or individuals with consistent high volumes of mail. General delivery is intended for people without a permanent address to receive their mail but does not focus on organizations needing to manage larger daily mail loads.