USPS Fraud & Tracking Collisions

What you need to know and how to protect your seller account

What’s happening

Fraudsters have increased attacks on USPS by creating and shipping counterfeit, unpaid shipping labels to get free shipping. This scheme—known as Mailer Identification (MID) fraud—is a growing industry issue affecting all USPS partners and platforms. A MID is a billing account number embedded in the tracking number printed on every USPS label. Fraudsters who understand the structure of USPS tracking numbers can extract this MID and use it to generate fake labels that look identical to those from legitimate shippers. 

Please note: this is an industry-wide USPS issue, not specific to Shippo or your account security.

We want you to have clear, official information and the right steps to protect your account if this happens to you. 

What we’ve observed

As a result of this scheme, you may see wrong or misleading tracking history on USPS.com. For example, a package you just shipped might already show as “delivered” in another state or display scans from places it’s never been. This happens when a fraudulent package with the same tracking number as yours is in the USPS mail stream, causing the tracking to combine events from both shipments.

• USPS has shared that, if you use a label that is the victim of MID fraud,  your package should still be delivered. 
• If your package does not arrive within 3–7 days, you can file a Missing Mail Search with USPS to have them investigate.

What you should do if you’re impacted 

If you see tracking activity that doesn’t match your shipment, notify both USPS and your Ecommerce platform right away. This helps your platform confirm the scans are part of a USPS-wide fraud issue and ensures your shipment record remains accurate.

1. Document the issue
Take screenshots of the USPS tracking page showing the incorrect scan(s).

2. Look for this tracking status
If you see “Delayed for postage assessment, held awaiting payment” on a legitimate package, it does not always indicate fraud. This status can appear temporarily when USPS has not yet processed the payment confirmation. In many cases, it resolves on its own within hours as the package continues through the network.

What to do:

• If the status clears within a day or two, no action is needed.
• If it remains for more than a couple of days, contact Shippo Support so we can investigate and work with USPS on your behalf.

In our experience, USPS typically releases these packages within 72 hours of notice.

3. Contact your selling platform

Let your platform know that the tracking history on USPS.com is showing incorrect information for your shipment.
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Include:

• Screenshots of the incorrect scans.
• Shipment details from the legitimate label you purchased.

Providing this information may help the platform understand that the issue is part of a USPS-wide MID fraud problem and not an error in your shipping process.

4. Contact Shippo Support
Share your case so we can log the impact and assist with your concerns. 

5. Follow USPS label usage guidelines
To avoid potential delays or intercepts, USPS recommends using labels within 30 days of purchase. This requirement has been part of our previous email communications and is also noted in our Help Center.

About USPS’s fraud mitigation efforts

In August 2024, USPS began a pilot program to identify and intercept unpaid packages entering the mail stream. To support this program, Shippo provides USPS with data verifying that each legitimate Shippo label has been fully paid. This ensures legitimate labels are validated quickly and accurately in USPS systems.

​​As of August 2025, USPS successfully completed its pilot phase of this program and is actively moving to fully enforcing fraud controls across their network.  The USPS reports that its fraud interception efforts are highly accurate and are expected to significantly reduce the number of fraudulent packages entering the mail stream. Their systems are designed to identify unpaid packages and remove them before delivery, while ensuring that all properly paid packages continue through the network and are delivered as normal.

Our commitment to you

We know your reputation as a seller is essential to your success, and that’s why we’re here to help protect it. We’re committed to:

• Giving you the tools and resources to handle questions from your selling platforms and customers with confidence.
• Working with USPS on your behalf to resolve tracking errors quickly.
• Making sure your shipments are recognized as legitimate in USPS systems.

Your business and your credibility matter to us. We’re here to help you every step of the way.

Resources

• Contact Shippo Support if you think you’ve been affected by USPS MID fraud.
• USPS Customer Service: 1-800-ASK-USPS (1-800-275-8777)

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