The US Postal service will process 607 million pieces of mail today, Monday, December 16th..
Many of those will be holiday cards and letters.
If you want to ensure your gifts get under the Christmas tree in time, the United States Postal Service says you must have the gift in the "First Class Mail" by Friday, December 20th.
For "Priority Mail," the deadline is Saturday, December 21st.
And the deadline for "Priority Mail Express" is Monday, December 23rd.