The post office is bracing for its busiest day of the year today.
The agency's busiest day is traditionally the Monday before Christmas as people mail cards and packages they prepared over the weekend.
Today is the last day to send holiday gifts through priority mail, and you have until midnight. Most Bay area post offices have extended hours this week. Senders can also use the Automated Postal Center, open 24 hours a day, 7 days a week.
Postal officials expect 800 million pieces of mail to be handled on Monday, 40 percent more than the average daily volume.
"There's still time to mail greeting cards and ship presents," Postmaster General Patrick R. Donahoe said in a statement. "If customers get their cards and packages to us by Tuesday, Dec. 21, we'll get them delivered by Christmas."
All post offices are closed on Christmas and New Years Day. The only items delivered on those days will be through express mail.