Does UPS Reuse Tracking Numbers? (All You Need to Know)

The ability to track a package is a modern convenience that is often taken for granted, and the way we can track each individual package is by using its tracking number.

So, does UPS reuse its tracking numbers, and if so, what does this mean for your UPS packages? If you’d like to find out, keep reading!

Does UPS Reuse Tracking Numbers In [currentyear]?

UPS reuses some tracking numbers in order to keep up with the massive volume of packages it handles in [currentyear]. These numbers will sometimes populate a past date for tracking info before the new package goes out, and overwrites the old information. Tracking numbers typically stay active for 120 days, and are recycled after 18-24 months, depending on package volume.

There’s a lot more to understand about how and why UPS tracking numbers get recycled, so be sure to keep reading to get more insight into this process!

How Long Do UPS Tracking Numbers Stay Active?

How long a tracking number stays active really depends on your definition of “active.”

The easiest way to think of what constitutes an active tracking number is whether or not the number still populates tracking information.

In this case, tracking numbers only stay active for about 120 days.

After the 120 day point, typing your tracking number into the UPS tracking page will no longer give you all of the package’s tracking number, only this notification:

“UPS could not locate the shipment details for this tracking number. Details are only available for shipments made within the last 120 days. Please verify your information.”

This notification also occasionally pops up when you’re trying to track a package that’s brand new, like something you’ve just ordered or just received a tracking number for.

If you see this message on a new package you’re trying to track, don’t panic!

There’s nothing wrong with your package or tracking information- this notification is actually a relatively common occurrence, especially in recent years.

What Happens to Old UPS Tracking Numbers?

What Happens to Old UPS Tracking Numbers?

UPS delivers something like 21 million packages per day, so there’s no way the company could come up with billions of unique tracking numbers to keep up with demand.

With this in mind, it makes sense that UPS would have to do something with its old tracking numbers, and what the company does is recycle them.

What this means is that any tracking number you’ve received from UPS is likely not a unique, individual number that’s used for your package only before being forgotten.

Instead, once tracking numbers have been inactive for anywhere from 18 months to 2 years, depending on the volume of packages UPS is handling, it will be recycled and used for another package.

To put this system in mathematical terms, individual shippers using UPS have a unique code that takes up 6 digits of the 16 digit tracking number.

UPS reserves an additional 3 digits of the 16 digit tracking number for the service code and check digit.

This leaves any given shipper using UPS 7 digits of the original 16 that can be automatically generated to make a unique tracking number.

7 unique digits translates to a million packages that this shipper can have in the UPS system.

So, once a shipper has sent more than one million packages using UPS, its tracking numbers begin to recycle.

Given the fact that UPS delivers around 21 million packages a day, it makes sense that tracking numbers would eventually have to be recycled in order to keep up with package volumes.

When a tracking number is recycled, there is sometimes some overlap between the old package and the new.

This means that if you were to enter in your tracking number before tracking on your new package has been updated, there’s a high likelihood that you’d receive a notification saying the number is more than 120 days old.

Once your new package is scanned in at a new facility, the tracking number will begin to populate information about the new package automatically.

Do UPS Tracking Numbers Change?

Tracking numbers do change, but only in limited circumstances.

Here are some reasons a tracking number can change while the package is in transit:

  • When a package is returned to sender after being deemed undeliverable due to missed delivery attempts, not being claimed after 5 business days at a pick-up location, etc
  • When the service level for a shipment changes, i.e a shipment going from UPS Next Day Air to UPS Next Day Air Early mid-shipment
  • If a shipment crosses an international border, and is handed off to a different shipping company such as that country’s postal service for delivery

If you’re concerned that your package’s tracking number will change while it’s in transit, be sure to reach out to the sender of the package.

Also, ask for any updated information to be forwarded to you, or call ups at 1-800-PICK-UPS.

To know more, you can also read our posts on whether or not UPS gives free boxes, if UPS updates tracking, and why is UPS slow.


UPS does recycle tracking numbers in order to help keep up with demand, as the company delivers nearly 21 million packages a day.

UPS tracking numbers stay “active,” as in populate tracking information, for 120 days after the last tracking update.

After 120 days, if you try to type the tracking number into the UPS website, you’ll receive a notification that the tracking number is no longer active.

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Marques Thomas

Marques Thomas graduated with a MBA in 2011. Since then, Marques has worked in the retail and consumer service industry as a manager, advisor, and marketer. Marques is also the head writer and founder of

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