Postal Letter

Can You Tell Which Type of Mail is Being Sent from the USPS Tracking Number Prefixes?

For example, tracking number starting with 9101 are Priority Mails within the United States, does anybody know the prefix 0403 denotes which mail? Or it's arbitrary, there's no connection between the tracking number prefixes and the type of mail?

Public Comments

1. Best I could tell it is arbitrary. The first 2 digits are called the Starter Code. I saw nothing that inidicated that they represented something particular, but I didn't read that much of it. Here is a link to Publication 91 which is the Confirmation Services Technical Guide. You are welcome to check it out and see what you find.
2. Well, got two things that may help.. First, the previous answer's document is a big help, if you can find it. Look on page 70 (also from 69-71) for a table showing what those codes are. 03 = Priority Mail/First-Class Mail [...] Package Services Delivery Confirmation Printed by the Postal Service 04 = Priority Mail & Package Services Delivery Confirmation USPS DELIVERY CONFIRMATION So, it looks like you have a USPS Priority/First Class mail package, with a shipping label printed by the USPS, instead of done online by the sender, and the package possibly has delivery confirmation. It's a government document, so it's incredibly ambiguous. Second, I too have an incoming package with the same 0403 prefix, and in this case, it's USPS Priority Mail. Now if it would just get here :) So, hope that helps.