You think you have a lot of holiday gifts and cards still to send? The U.S. Postal Service expects to move about 658 million pieces of mail today on what officials believe will be the service’s busiest day of the year.

While it’s forecast to be the busiest day of the year, it isn’t the last day to get your gifts and cards in the mail and delivered by Christmas.

Those deadlines begin rolling in pretty rapidly though starting Thursday, Dec. 20, with the deadline to get first class mail to its destination. You have another day to get packages out via Priority Mail. Saturday is the Express Mail deadline, according to the USPS.

It seems that most people are ahead of the curve, by the USPS calculations. Today is both the biggest mailing day for holiday cards and packages.

Check your mailboxes Wednesday, that’s the busiest delivery day for holiday cards. The biggest delivery day for holiday packages is Thursday.

Some more mail by the numbers:

• 237 - Number of years U.S. Postal Service has been delivering holiday cheer

• 17.9 billion - Amount of cards, letters and packages to be delivered between Thanksgiving and New Year’s Eve

• 658 million - Number of pieces of mail processed on Dec. 17, the busiest mailing day of 2012

• 528 million - Average number of pieces of mail processed daily

• 560 million - Average number of pieces of mail processed daily during the holidays

For further information on the 2012 Holiday Shipping Deadlines please go to usps.com/shippingdates/welcome.htm.