Although U.S. imports held steady over 2025, taken as a whole, a series of tariff-driven surges and slowdowns reshaped the flow of cargo throughout the year.

According to data from Descartes, imports at major U.S. ports remained largely unchanged between 2024 and 2025, declining by just 0.03%. However, that masked sharp swings in monthly volumes, as importers rushed shipments ahead of sudden tariff hikes, and pulled back just as quickly once duties took effect.

"2025 will surely be remembered as the year U.S. tariffs rewrote the global trade playbook," Descartes said in its Top 30 U.S. Ports report released on April 28.

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Descartes tracked a series of unseasonable peaks and valleys for import volumes through the year, which correlated with President Donald Trump's "Liberation Day" tariff announcement in April, May's trade truce between the U.S. and China, and then a late-summer period when companies front-loaded shipments ahead of reciprocal tariffs that took effect against dozens of nations in August. Much of that volatility came from swings in shipments from China, which rose and fell alongside tariff changes, and largely dictated the overall pattern of imports for the year.

The West Coast was especially vulnerable, given that China-sourced shipments accounted for nearly half of the region's import volumes in 2025, compared to 26% at Gulf ports and 22% into East Coast ports. A flurry of other trade deals and new tariffs involving other nations created even more swings, as shippers and importers rushed to defer or move up orders in response to a constantly-shifting trade landscape.

That shift also changed routing patterns, with more cargo moving through West Coast ports than any other region during the late summer surge, as importers prioritized faster Asia routes to ensure that shipments would arrive before planned tariffs were scheduled to take effect in August. After that, East Coast ports took in the largest share of imports, narrowly edging out the West Coast by the year's end as import volumes leveled off in the fall and winter months.