overnight envelope usps

overnight envelope usps refers to the use of USPS Priority Mail Express for sending urgent documents or small items overnight. This service guarantees delivery by 10:30 AM the next day (or in some cases, by 12:00 PM) to most destinations. Overnight envelope shipping is ideal for sending time-sensitive materials, such as legal documents, contracts, or personal correspondence. Priority Mail Express envelopes are available for a flat rate, making it a convenient option for those needing quick delivery.