The United States Postal Service sells several additional services, like certified mail and delivery confirmation, that allow customers to track their letters so they know when they have been delivered. Though these services cost a small extra fee, they can be especially useful when you are sending documents you want a record of the addressee receiving, such as tax returns sent to the IRS.
Purchase a tracking service from the USPS when you mail your letter at the local post office. A tag will be placed on the letter and you will be given an identifying code.
Track the status of your letter through the USPS track-and-confirm website at USPS.com or by calling the USPS at (800) 222-1811.
Sign up for email notifications concerning your package on the USPS website. After you have entered your tracking number, click "Go" on the right of "Track & Confirm by Email." Enter your name, email address and that you want to receive notifications of future activity for your letter and click "Submit." You will now get emails updating your status tracking.
The information for letters is updated each evening so there is no need to refresh the tracking information several times per day.
You cannot retroactively add any tracking services to your letter after it has been shipped so make sure that you purchase the services before mailing if you need it.