USPS Tracking is the Postal Service’s free scan-based tracking service: each trackable item gets a unique barcode and tracking number, and every scan from acceptance to delivery shows up on USPS.com. It’s included at no extra charge with Priority Mail, Priority Mail Express, USPS Ground Advantage and most other package services, but not with First-Class Mail letters and flats.
This page explains how USPS Tracking works, which services include it, where to find your number and what to do when tracking stops updating. For step-by-step tracking help, see our complete USPS tracking guide.
How Does USPS Tracking Work?
USPS Tracking works by scanning the barcode on your label at key points in the mail network. The first scan happens when USPS accepts the item at a Post Office counter, from a pickup, or at a drop-off point. More scans follow as it moves through processing facilities, then when it’s out for delivery, and finally when the carrier delivers it or leaves a notice.
Each scan creates a status update tied to your tracking number, such as “Accepted,” “In Transit,” “Out for Delivery” or “Delivered.” Our guide to USPS tracking status meanings explains each one. Not every handoff produces a scan, so a package can travel for a day or more without a new update and still be on schedule.
Which USPS Services Include Free Tracking?
USPS provides USPS Tracking at no additional charge on all eligible products except USPS Marketing Mail. The main services that include it are:
| Service | USPS Tracking | Delivery time |
|---|---|---|
| Priority Mail Express | Included | 1–2 days |
| Priority Mail | Included | 1–3 business days |
| USPS Ground Advantage | Included | 2–5 days |
| Media Mail and Library Mail | Included | Slower, ground-based |
| First-Class Mail letters and flats | Not available (add Certified Mail or another trackable extra service) | 1–5 days |
If you want tracking on a letter or large envelope, add an extra service that includes it, such as Certified Mail. If you’re shipping a small item, sending it as a USPS Ground Advantage package gets you tracking and $100 of insurance included. Delivery times vary by distance; our guide on how long Priority Mail takes breaks down that service’s delivery windows.
Where Do You Find a USPS Tracking Number?
Your tracking number is under the barcode on the shipping label, on your Post Office receipt, and in the confirmation email if you bought the label online. Domestic USPS tracking numbers are usually 22 digits, while international items use 13 characters, such as two letters, nine digits and “US.” Our guide to what a USPS tracking number starts with shows the common formats.
If you’re the recipient, ask the sender for the number. If you’ve lost it, look up your USPS tracking history through your USPS.com account or Informed Delivery, or contact USPS tracking number customer service for help.
How Do You Track a USPS Package?
You can check a USPS tracking number in several ways:
- USPS.com: enter the number on the USPS Tracking page; you can enter several numbers at once, separated by commas.
- USPS Mobile app: track and save packages and turn on notifications.
- Text and email updates: sign up on the tracking results page to get updates as the status changes.
- Informed Delivery: a free USPS service that shows incoming packages for your address on one dashboard, plus previews of letter mail.
- QR codes: some receipts and labels can be scanned with a phone; see our USPS tracking QR code tips.
How Long Does USPS Keep Tracking History?
USPS keeps tracking information for items without a signature for 120 days, and for items with a signature service for 2 years. If you need records longer, USPS Tracking Plus is a paid add-on that extends access anywhere from an additional 6 months up to 10 years for domestic items.
Tracking Plus is useful for businesses that need proof of delivery for disputes, audits or legal records. For most personal shipments, a screenshot of the “Delivered” page is enough.
What If USPS Tracking Isn’t Updating?
A tracking number may show no information for up to a day after the label is created, until USPS scans the item at acceptance. After that, gaps of a day or two between scans are common, especially over weekends and holidays. If your package shows “Label Created” long after you dropped it off, see our guide to USPS tracking not updating after drop-off.
If tracking hasn’t changed for several days past the expected delivery date, start with our guide to USPS tracking not updating, then submit a Missing Mail search on USPS.com. Our guide to USPS tracking for a lost package covers searches and insurance claims.
Labels bought through ParcelPath carry the same USPS Tracking as labels bought at the Post Office, along with discounted postage of up to 89% off retail. You can compare USPS and UPS rates for your next package in the ParcelPath rate calculator.
Frequently Asked Questions
Is USPS Tracking free?
Yes. USPS includes USPS Tracking at no additional charge on all eligible products except USPS Marketing Mail, including Priority Mail, Priority Mail Express and USPS Ground Advantage. It isn’t available on First-Class Mail letters and flats, which need an extra service such as Certified Mail to be tracked. Tracking Plus, which extends history, costs extra.
How long does USPS tracking history stay available?
USPS keeps tracking information for 120 days for items without a signature, and 2 years for items mailed with a signature service. To keep records longer, USPS Tracking Plus extends access from an additional 6 months up to 10 years for domestic items. Save a screenshot if you may need proof of delivery later.
Can you track a USPS letter?
Not with a stamp alone. USPS Tracking isn’t available for First-Class Mail letters and flats. To track a letter, add an extra service that includes tracking, such as Certified Mail, or send it as a package with USPS Ground Advantage or Priority Mail, which include tracking at no extra charge.
How many digits is a USPS tracking number?
Most domestic USPS tracking numbers are 22 digits, often printed in groups of four under the barcode. International items use 13 characters: two letters, nine digits and two letters, ending in “US” for items mailed from the United States. Shorter numbers on a receipt, such as the transaction number, aren’t tracking numbers.
Why does my USPS tracking number say not found?
Usually because USPS hasn’t scanned the item yet. A new number may not show information until the package is accepted, which can take up to a day after the label is created. Check that you entered every digit correctly. If it still shows nothing a few days after drop-off, contact the sender or USPS.
Sources
- USPS Domestic Mail Manual 503: Extra Services (USPS Tracking eligibility)
- USPS FAQ: USPS Tracking Plus, The Basics (history retention)
- USPS: USPS Ground Advantage (included tracking and insurance)
- USPS Tracking
Part of our USPS Tracking guide. Related: USPS Tracking and Delivery, USPS Tracking Not Updating, USPS Tracking Not Updating After Drop Off.
