USPS Commercial Base Pricing is the standard discounted rate offered to USPS customers, who buy and print shipping labels online. Compared to retail rates given at the post office, Commercial Base Pricing is significantly discounted. Unlike USPS Cubic Pricing, there is no volume requirement, so you can just sign up and get Commercial Base Pricing rates. Commercial Base Pricing is available for the following USPS mail classes: First Class Mail, Priority Mail, Priority Mail Express, First Class Package International, Priority Mail International, and Priority Mail Express International.