UPS, FedEx cap air express deliveries: WSJ

United Parcel Service and FedEx started limiting air express deliveries after a last-minute increase in shipped packages caused some retailers to exceed agreed-upon limits, The Wall Street Journal reported, citing people briefed on the situation.

This year, both UPS and FedEx held some retailers to their volume commitments during the final shopping days before Christmas, aiming to avoid a repeat of a fiasco last year, the Journal reported.

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"As we've moved through the peak season there have been some shifts in demand and customer needs as a result of slowdowns at the West Coast ports," said Bonny Harrison, a spokeswoman for FedEx.

UPS cargo planes in Louisville, KY.
Jodi Gralnick | CNBC
UPS cargo planes in Louisville, KY.

Harrison added that these changes resulted in some caps on volume.

A UPS spokeswoman said that company's operations were going as planned.

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Both UPS and FedEx had previously told Reuters that if unplanned package volumes threatened to overload their systems, they could refuse to take them.

UPS told Reuters in November that customers could end up being charged more for unplanned late surges.

A late spike in demand last year caused by last-minute online promotions plagued express delivery companies. Some 2 million express packages were left stranded by delivery companies on Christmas Eve, according to shipment-tracking software developer ShipMatrix Inc.