Which extra service is permitted with Priority Mail Express?

Priority Mail Express offers a variety of extra services to enhance the shipping experience, and one of the distinctive features is the option for Collect on Delivery (COD). This service allows the sender to specify that the recipient must pay a certain amount upon delivery, which is collected by the USPS. This can be particularly useful for transactions where payment needs to be confirmed before the package is released to the recipient.

The availability of COD with Priority Mail Express supports time-sensitive and valuable shipments, making it a suitable choice for businesses and individuals looking to ensure payment upon delivery. Other choices such as overnight delivery and Priority Flat Rate are actually standard features of Priority Mail Express rather than extra services, while ground delivery is not part of the Priority Mail Express service, which is primarily focused on expedited handling and shipping.