Dec. 15 is the deadline for UPS, FedEx, USPS ground delivery by Christmas Day

A FedEx worker wears a face mask while loading a truck on Fifth Avenue in NYC.(Photo by Noam Galai/Getty Images)

Time is running out for gift-givers to get their packages delivered by Christmas Day. 

FedEx, USPS and UPS said Dec. 15 is the recommended deadline for people to choose ground delivery to ship their gifts in order to have delivered by Christmas Day in the United States. 

FedEx said after Dec. 15, customers should probably pay for freight, overnight or 2-day shipping. The last option would be same-day delivery in the same city on Dec. 25.

“We are warmed up for what we’re calling the ship-a-thon,” said Brie Carere, chief marketing and communications officer at FedEx. “Like everything else in 2020, this is going to be an unprecedented peak season. We’ve actually seen three years of growth in e-commerce pulled forward. So we are expecting a ton of volume.”

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UPS said after Dec. 15, customers should opt to pay for next day, 2-day or 3-day shipping. Only UPS Express Critical is an available option on Christmas Day.

USPS recommended customers pay for priority or first-class mail after Dec. 15 if they want their gifts delivered by Christmas.

FedEx and UPS are ramping up their holiday hiring while expanding their weekend operations and asking retailers to use their shipping network when there is more slack. And stores are pushing shoppers to buy early and are expanding services like curbside pickup to minimize the need for delivery.

Amazon, which has been growing its own delivery network so it doesn’t have to rely as much on UPS and the U.S. Postal Service, is nonetheless warning shoppers not to wait until the last minute to buy gifts. While the world’s largest online retailer delivers more than half of its packages itself, it still relies on other carriers to get orders to shoppers.

U.S. online holiday sales are expected to shatter previous records. Adobe Analytics, which measures sales at 80 of the top 100 U.S. online retailers, predicts a total of $189 billion in online holiday sales, a 33% increase compared to last year. That’s equal to two years worth of holiday e-commerce sales growth shoved into one season.

The Associated Press contributed to this report. This story was reported from Los Angeles.