how fast is priority mail usps is a commonly asked question for customers who need fast delivery. USPS Priority Mail offers delivery within 1 to 3 business days, depending on the origin and destination of the package. This service is ideal for sending packages that need to arrive quickly but do not require overnight delivery. USPS Priority Mail also includes tracking and insurance for packages up to $50, making it a reliable and cost-effective shipping option for time-sensitive deliveries.