priority mail cost refers to the rates associated with USPS Priority Mail services, which offer faster delivery times compared to standard mail options. The cost of Priority Mail is determined by the weight, size, and destination of the package. For example, the cost of shipping a small flat-rate box is $8.95, while larger flat-rate boxes can range from $15 to $25. USPS also offers regional rate boxes, which allow for lower rates based on proximity. Priority Mail includes features such as free tracking, up to $50 in insurance, and guaranteed delivery within 1-3 business days, making it a popular option for time-sensitive shipments.