Still working on your taxes?
This year, your return is considered filed on time if it's postmarked by midnight April 18.
Some post offices across the Washington, D.C. region will be open late to accommodate last-minute filers. Click here for a list. A few are open until 10 PM.
Also, make sure you've got the right amount of postage, especially if you did a lot of itemizing. Those extra sheets of paper add a lot of weight. Tax collectors do not pay any postage that's due.
The cost for all first-class letters up to 1 ounce is 44 cents.