FedEx predicts a record-breaking day Monday as 19 million packages get shipped.
Measured another way, that's 200 packages per second, FedEx said in a prepared statement.
United Parcel Service says its biggest shipping day will be Dec. 20, with an estimated 28 million packages sent worldwide, about 300 per second.
On a standard day, UPS ships about 16 million packages. On Dec. 18, UPS estimates that it will have 69 million or more tracking requests.
FedEx said the deadline for pre-Christmas delivery via FedEx Ground is December 17. FedEx Express packages should be sent by Dec. 22.
Plan on at least seven days for UPS ground shipping in the two weeks leading up to Christmas. UPS 2nd Day Air remains just that.