What class of mail does the Postal Office have a monopoly on?

The Postal Service has a monopoly on the delivery of First-Class Mail. This monopoly is established under federal law, which grants the USPS exclusive rights to provide this particular class of mail. First-Class Mail includes items such as letters, postcards, and small parcels that are often time-sensitive, ensuring that they receive priority handling. This exclusivity helps maintain standardized service rates and delivery times across the nation.

In contrast, other classes of mail, such as Marketing Mail and Priority Mail, can be offered by private carriers and do not have the same legal protections or monopoly status as First-Class Mail. Thus, while the Postal Service offers various mailing services, the monopoly specifically pertains to the First-Class Mail class, emphasizing the importance of reliable service for essential communications.