jetcityimage/iStock(NEW YORK) — If you don’t want to end up paying extra, now’s the time to send your holiday letters and packages to get them to their destinations in time for Christmas.Friday marks the last day you can send your items through the U.S. Postal Service’s First Class mail service and expect them to be delivered by Dec. 25. Come Saturday, you will have to shell out more money for Priority Mail service.This week is projected to be the busiest one of the holiday season for the USPS. The agency expects to deliver close to 2.5 billion pieces of mail this week alone.Copyright © 2019, ABC Audio. All rights reserved.