The partnership once played a major role in Amazon's rapid expansion while generating billions in yearly revenue for USPS. The decision comes as the Postal Service continues to struggle financially, including a reported $9.5 billion loss in its most recent fiscal year.

For much of Amazon's growth, USPS provided nationwide coverage, especially in rural and remote areas where private carriers often cannot operate profitably. That reach allowed Amazon to deliver to virtually every address in the country, making the arrangement one of the largest public-private logistics partnerships in U.S. history. Recent contract negotiations and changes to USPS pricing appear to have pushed Amazon toward a different approach. Instead of renewing the agreement, the company is shifting more deliveries to its own expanding logistics network, tightening its control over speed, cost, and customer experience.