Today, Post Offices around the United States are going open late like until midnight just to give way to IRS Tax filing. People have this bad habit of doing things the last minute, therefore, congesting our post offices. Meanwhile, if you think you will be late in filing, you can check out the IRS web site and download the File Extension Online form 2009.
If you want to know on what time your post office closes, you may call your local mailing office post or check out their website online. They are extending their services usually up to midnight and hire extra man power to accommodate the many requests for the post to be open right now.