The Port of Los Angeles said import container volume rose 16.5% in June from a year ago.
Loaded imported containers rose to 382,666 20-foot equivalent units, and outbound containers rose 8.5% to 160,823 TEUs.
Total cargo for June increased 13.9% to 736,426 TEUs, the largest volume in monthly containers since September 2012.
Year-to-date, volume is up 9.2% from the same period last year to 4 million TEUs, the port said.
The Port of Los Angeles and neighboring Port of Long Beach make up the largest U.S. container port complex.