us post office priority refers to the USPS Priority Mail service, a popular shipping option for faster delivery within the United States. Priority Mail offers delivery in 1-3 business days, depending on the distance between the sender and recipient. This service includes features like tracking, insurance, and free packaging, making it a reliable option for sending important documents, packages, or gifts. USPS Priority Mail is often used by businesses and individuals who need to ensure timely deliveries without paying the higher costs of expedited services like Express Mail.