Military spouses and children who have U.S. lawful permanent residence (green cards) have some special rights under U.S. immigration laws when it comes to apply for U.S. citizenship (naturalization).
For example, you may be able to count time spent abroad toward your U.S. residency requirements, or gain immediate citizenship if your spouse is killed in action.
To be considered is performing military service, your spouse most have been on active or reserve duty in the U.S. Army, Navy, Marines, Air Force, or Coast Guard, or in a National Guard unit while the unit was federally recognized as a reserve component of the U.S. Armed Forces. (See 8 C.F.R Section 328.1.)
Among the many requirements for green card holders applying for U.S. citizenship is that you have not only had permanent residence for a certain number of years (in most cases, five) but have spent at least half of those years physically present in the United States.
That could be a difficult requirement to meet if you are married to a U.S. citizen who is serving in the military and is stationed abroad. However, if you (by official military order) accompanied your spouse on this overseas posting, a special exception allows you to count your time living abroad with your spouse as if you were in the United States. (Immigration and Nationality Act or I.N.A. Section 319(e), 8 U.S.C. Section 1430(e); and I.N.A. Section 284(b), 8 U.S.C. Section 1354(b)).
You can take additionally advantage of an exception allowing spouses of U.S. citizens to apply for citizenship after only three years of permanent residence.
If you plan to make use of this exception, you'll need to obtain a signed and completed Form DD-1278, "Certificate of Overseas Assignment to Support Application to File Petition for Naturalization" from the appropriate military official. This form certifies that you have “concurrent travel orders” and are authorized to join your military spouse abroad.
Unlike most applicants, you, as a military spouse, won't need to return to the United States to apply for naturalization if you don't want to. You are allowed to instead complete the naturalization process abroad.
To apply for citizenship, you'll need to file USCIS Form N-400. The instructions with the form will give you the latest information on where to file and what fee you'll owe.
If you have a green card and your U.S. citizen spouse, child, or parent dies while serving honorably on active duty with the U.S. Armed Forces, and (if you're a spouse) the two of you were married and living together at the time of death, you can apply for citizenship right away. There's no need to wait to fulfill the usual three- or five-years’ permanent residence requirement. (See I.N.A. Section 319(d), 8 U.S.C. Section 1430(d).)
This section of the law also works for people whose spouse or parent was granted U.S. citizenship posthumously (after death) under I.N.A. Section 329A.
You'll still need to meet the general naturalization requirements, however, such as being 18 years old, being able to speak, read, and write English, showing good moral character, and passing a test on U.S. history and government.