What is the recommended action for urgent envelopes that must arrive by the next day?

Choosing Express Mail for urgent envelopes that must arrive by the next day is the best course of action because it is specifically designed for expedited delivery. Express Mail offers the fastest service provided by the postal service, ensuring that documents can be delivered overnight to various destinations. This service typically includes guaranteed delivery by a certain time and tracking features, which are essential components when timing is critical.

In contrast, Standard Shipping, Priority Mail, and Parcel Post do not have the same level of urgency associated with them. While Priority Mail can deliver within one to three business days, it does not guarantee next-day delivery, making it less suitable for time-sensitive materials. Similarly, Standard Shipping and Parcel Post are generally slower and meant for less urgent deliveries, often taking longer than Priority Mail and lacking the time-sensitive focus required for urgent items. Therefore, for urgent envelopes that have a strict next-day requirement, Express Mail is the appropriate and recommended service.