With just six days left until Christmas, the U.S. Postal Service is kicking their work getting cards and gifts across the country into high gear.
Despite it being a traditional day off, many post offices remained open Sunday to keep the mail flowing as the holiday approaches.
The USPS says that time is of the essence if you want your holiday gifts to arrive on time.
They say that first-class mail should be sent by Tuesday if you want it to arrive at its destination by Christmas.
Priority Mail should be sent out by Wednesday and Express Mail by Thursday, the agency says.