Thousands of people will mail cards and packages from post offices across the country.

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“I tend to come here early, get everything mailed out and I'm done with it,” said Jacque Butts.

It’s a routine she is used to this time of year.

“I have everything I need for Christmas. Everything is bought; already shipped out,” said Butts.

And she is just in time, especially since Dec. 15 is typically the busiest mailing day of year. The U.S. Postal Service says more than 640 million packages will be shipped out today. Butts says she got everything out the way.

Gordon Richards followed suit. He wasn’t sure about the deadline, but he wants to make sure one gift in particularwill make it on time.

“One goes to my son in boot camp up in Great Lakes, so I wanted to make sure that got there in time,” said Richards.

If you want your packages to arrive by Christmas, using standard post, you need to mail them by Monday, Dec.15. If you are willing to pay more, you can wait until Dec. 23, but you’ll have to ship using Priority Mail Express.