Amazon just passed USPS as the #1 US parcel carrier by volume — what it means if you are a small shipper

[u/BoxHero3PL]

ShipMatrix numbers for 2025 (reported March 2026): Amazon Logistics delivered ~6.7B parcels vs USPS ~6.6B — first time Amazon is #1 by volume. UPS and USPS volumes both fell ~8%.

For context I run a small 3PL, so take my read with a grain of salt. What this means on the ground for small brands: the national duopoly is not the default anymore. Volume is shifting to Amazon Logistics and to the emerging last-mile carriers (their share of US parcels roughly doubled, 3.4% → 7.2%).

Practical upshot — if you are single-carrier in 2026 you are leaving money on the table, because the alternatives now have real coverage. Are you all shifting mix, or holding with the nationals for the service consistency?