Amazon Prime is fast, reliable, and everywhere—but who’s actually delivering the box that lands on your doorstep? If you’re seeing USPS tracking numbers show up with Prime orders, you’re not alone. And yes, Amazon still uses the United States Postal Service in 2025.
But that’s only part of the story.
Here’s how Prime shipping works today—and why it matters for sellers using FBA, FBM, or Seller Fulfilled Prime.
Amazon’s Hybrid Delivery Network: It’s Not Just USPS
Amazon doesn’t rely on a single carrier anymore. Instead, it operates what’s known as a multi-carrier, last-mile delivery model, where each package is routed through the most efficient method based on destination, delivery speed, and fulfillment type.
Here’s the typical mix:
- Amazon Logistics (AMZL): Amazon’s own fleet of vans, DSP drivers, and Flex contractors
- USPS: Still widely used for rural delivery, PO boxes, and Sunday/holiday service
- UPS / FedEx / regional couriers: Fill gaps in high-volume metro areas
That means even Prime orders can be handed off to USPS depending on geography, staffing, or seasonal capacity. In fact, Amazon is one of USPS’s largest shipping partners, and that relationship continues in 2025.
When Does Amazon Use USPS for Prime Orders?
Here’s when your Prime order is likely to be delivered by USPS:
- Rural addresses where AMZL or Flex isn’t available
- Sundays and holidays, when USPS offers last-mile delivery support
- Low-weight items that qualify for USPS’s commercial shipping rates
- Overflow periods like Prime Day or Q4 when Amazon needs extra capacity
In most cases, Amazon injects packages into the USPS system from its own sortation centers, which USPS then delivers as part of its final mile network.
What This Means for FBA Sellers
If you’re using Fulfilled by Amazon (FBA), USPS is just one of several carriers your orders may be routed through. You don’t choose the carrier—Amazon does. But here’s what’s important:
- USPS is often used for lighter, smaller, lower-cost items
- FBA sellers benefit from Amazon’s negotiated commercial USPS rates
- You’ll still meet Prime delivery standards without lifting a finger
It’s seamless—but worth understanding in case customers report USPS-specific issues or tracking quirks.
What About FBM and Seller Fulfilled Prime?
If you’re a Fulfilled by Merchant (FBM) seller or running Seller Fulfilled Prime (SFP), you’re on the hook for shipping. That means:
- You can (and should) consider USPS for fast, affordable service
- SFP requires meeting strict Prime shipping performance metrics
- USPS works well for lightweight SKUs, especially if you’re using tools like Pirate Ship or ShipStation to get bulk rates
USPS is often the best choice when you’re looking to hit 1- to 2-day delivery promises without UPS/FedEx pricing.
Why Sellers Should Still Care in 2025
Even if you’re fully FBA, understanding how Amazon uses USPS helps with:
- Customer service: Know how to respond when buyers ask “Why is USPS delivering this?”
- Returns: USPS may handle your return shipments
- Labeling & packaging: If you’re prepping your own inventory for FBA, packaging requirements may vary depending on how it’s delivered
Plus, if you ever switch to FBM or hybrid fulfillment, USPS becomes part of your toolkit.
Bottom Line: USPS Is Still a Big Part of Amazon Prime Delivery
Amazon’s logistics empire keeps growing, but the Postal Service still plays a vital role—especially in rural delivery zones and during peak volume periods. For sellers, it’s part of a larger shipping puzzle that affects how quickly and efficiently your products reach customers.
If you’re not actively thinking about fulfillment strategy—FBA vs FBM, last-mile reliability, and cost control—you’re probably leaking margin or leaving performance on the table.
Need help with your shipping strategy or prepping for SFP or FBA scale?
At Space Command, we help sellers navigate the real logistics behind Amazon success. Whether you need to streamline fulfillment, scale faster, or stop getting penalized by delivery metrics—we can help.
Let’s fix what’s slowing you down.
FAQ
Does Amazon Prime still use USPS?
Yes. USPS handles many last-mile Prime deliveries—especially in rural areas or on Sundays.
Can I use USPS if I fulfill my own Amazon orders?
Yes, USPS is one of the most popular carriers for FBM and SFP sellers. It’s affordable and widely integrated with Amazon’s shipping tools.
Do FBA sellers need to worry about USPS?
Not directly—Amazon chooses the carrier. But it’s good to understand the full picture, especially when troubleshooting delivery delays or preparing for hybrid fulfillment.
Why does my Amazon package show a USPS tracking number?
Because Amazon handed off the package to USPS for final delivery. This is common and part of their logistics model.