Tax day is here, but service members who have yet to file may be better served by following these steps than by rushing through their returns to meet the deadline, and possibly making costly mistakes:

1. Contact MilTax. If you're struggling through the paperwork or you've stumbled upon a last-minute question, you can get free tax help courtesy of this program. Visit the MilTax website for free tax filing software and a number of tip sheets, or call MilTax anytime at 800-342-9647. If you've already received an extension, you can still get help with your returns at that number from 8 a.m. to 10 p.m. Eastern time, Monday through Friday, beginning April 19.

2. File an extension. IRS Form 4868 (download the .pdf), which can be filed electronically, will land you an automatic extension, with a couple of caveats. Chief among them: The form must be filed today, and if you don't send a tax payment today, you'll have to pay interest and penalties on any taxes you owe. You can also get an extension by paying all or part of your estimated income tax due, if you indicate that the payment is for an extension -- that way, you won't have to file a separate extension form. Learn more at  this IRS page. 

3. Overseas relief. If you're stationed out of the country, you automatically qualify for a two-month extension and have the option to extend that deadline another four months. Thinking of stretching it further, or putting it off until your next assignment? Think again: Additional extensions are rarely granted in such situations, according to the MilTax website.

4. Check for combat extensions. Service members deployed to a combat zone who returned home less than 180 days before the tax deadline are eligible for an automatic extension. Those who were hospitalized after their deployment may have even longer to pay. Check the IRS rules on qualifying duty to see if you're covered, or call MilTax for assistance.