FedEx expects it will move about 19 million packages through its ground, express, and freight networks on "Green Monday," or about 10 percent more than it did last year on the second Monday of December.
Mirroring the increase in online shopping, FedEx has continued to see big gains in the volume on its busiest day of the year. This year's estimate is nearly double its volume in 2005.
Despite the record volume, FedEx said it plans to hire 20,000 seasonal workers, or about the same as last year, to deal with the boost in volume. However, the company has been hiring staff throughout 2012, especially at its Ground and SmartPost division, which will handle the bulk of the holiday volume.
The forecast also was already incorporated into the company's fiscal 2013 earnings outlook, the company said.
Almost $1 out of every $10 of consumer discretionary spending is now done online, according to ComScore.
Although the National Retail Federation, the retail industry's trade group, expects holiday sales growth to moderate and rise only 4.1 percent this year, online spending is expected to maintain its robust pace. EMarketer estimates online holiday sales, excluding travel, will be up 16.8 percent from last year to as much as $54.5 billion. (Read More: Retail Trade Group Sees Holiday Sales Up 4.1%.)
The growth reflects the fact that a record number of shoppers are expected to buy gifts online. According to a NRF survey, some 51.8 percent of all consumers plan to buy some gifts and holiday items online, up from 46.7 percent last year.
Also, the average person expects to buy a greater portion of their gifts online. Shoppers expect to complete about 38.8 percent of their shopping online, another high in the history of the NRF survey.
UPS, the largest packaged delivery company, hasn't weighed in on its outlook for the Christmas holiday season yet. But the company reports its earnings on Tuesday, and it may comment on its seasonal hiring plans at that time. Last year, UPS added 55,000 workers during the holidays, or 10 percent more than it hired in 2010.
—By Christina Cheddar Berk, CNBC.com News Editor; Reach Her on Twitter @ccheddarberk
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