When you apply for naturalized U.S. citizenship, the U.S. government wants to make sure you have closer ties to the United States than to any other country. One of the ways it does this is through rules relating to your residence and presence in the U.S., both past and present. If you are now or have been absent from the United States since becoming a permanent resident (a green card holder), you need to be aware of five different citizenship rules that most applicants must comply with, concerning:
We'll discuss each of these below. This article does not, however, discuss any of the ways you might be exempt from some or all of these rules.
One cannot apply to become a U.S. citizen without first being a lawful permanent resident of the United States (an LPR). When you apply, U.S. Citizenship and Immigration Services (USCIS) will check to make sure you didn't abandon your permanent residence at some point by spending too much time outside the United States (a serious risk for LPRs).
U.S. immigration authorities can decide you abandoned your permanent residence if you moved to another country intending to live there permanently, or if you left the United States and remained outside it for a long time (typically more than six months). There's no set period of time that you can stay outside the United States and feel safe, however. It's more a question of whether you intended your trip to be temporary. Still, any trip that lasted six months or less won't ordinarily be questioned.
Normally the biggest hurdle will be when you actually return to the United States, and interact with an officer of Customs and Border Protection (CBP). The officer who greets you ask questions to examine whether you abandoned your permanent residence if you took a trip for more than six months, and you really have some explaining to do if your trip lasted more than a year. They CBP officer will look at the reason for your trip, how long you intended to be gone, and what caused you to be gone so long. You can also abandon your permanent residence by multiple trips, no matter how long, if you don't really spend much total time in the United States at all.
But the fact that you made it back into the United States is no guarantee that USCIS won't take another look when you apply for naturalization, and decide that you did, in fact, abandon your U.S. residence.
The general rule is that you must have five years of continuous (unbroken) residence in the United States right before applying for citizenship, and also before attending your oath ceremony. The rule changes to three years for people who are married to and living with a U.S. citizen spouse up to the time they're sworn in as U.S. citizens.
To have continuous residence, your permanent dwelling place must have been in the United States. USCIS looks at the place you actually lived. If you lived overseas, it doesn't matter if you considered your main residence to be in the United States or if you always had plans to move back.
USCIS will presume that you broke your continuous residence if you were gone from the United States for more than six months during the five years before applying. You can, in the course of applying for citizenship, convince USCIS that your absence didn't break your continuous residence. To do so, you'll want to show evidence that, for example, you kept your job in the United States and didn't take a job overseas when you were gone, that your family stayed in the U.S. when you were gone, that you kept a place to live in the U.S. for when you returned, and more about your ties to the United States.
If you were gone for a continuous period of one year or more during the five- (or three-) year period, your continuous residence was broken. You can't try to convince USCIS otherwise. You'll have to wait until you've been back in the U.S., living there continuously for four (or two) years and a day before applying for citizenship. (You don't have to wait the full five (or three) years, because even if you leave again, you can't possibly be gone for a whole year by the time you apply. But it's best not to leave again for more than six months.)
If you broke your continuous residence by living outside the United States, you will have to wait to apply for citizenship. (For details, see When Can I Apply for U.S. Citizenship?)
You must be physically present in the United States during at least half of your required years of continuous residence. That's a minimum of two and a half years before you apply and before you take your oath if you need to complete five years as an LPR, or one and a half years for spouses of U.S. citizens who must complete three years as an LPR.
The days do not have to be continuous in any way. USCIS is just going to look at the last five (or three) years and count the number of days you spent inside the United States. Even if you preserved your continuous residence by not staying outside the U.S. for more than six months or a year at a time, multiple shorter trips could be a problem for the physical presence requirement.
The day you leave the U.S. and the day you return are counted as days of physical presence within the U.S. for citizenship purposes.
What if you're stranded outside the U.S., and the total days of your absence are about to add up to have of your required physical presence time? One possibility is to quickly submit your naturalization application from abroad, so as to lock in your time as of the date your application is received by USCIS.
When you apply for naturalized U.S. citizenship, you must have lived in your state or in the USCIS service district where you apply for at least three months beforehand. If, for example, you've been living outside the United States, you can't immediately apply for U.S. citizenship when you move back.
You need to decide where you want your U.S. citizenship interview and oath ceremony to take place, and live in that state or USCIS service district for at least three months before submitting your Form N-400. If you move later, you can ask that your interview location be changed.
If you're coming back to your former residence in the United States after having been outside the country for less than a year, you can apply right away, as long as you had been living there (or in that state or USCIS service district) for three months before you left the United States.
If you're going to school outside your state or USCIS service district, you can apply for U.S. citizenship where your school is located, or where your parents live, if you're financially dependent on them at the time of filing and during the whole citizenship application process.
After you apply for citizenship, USCIS needs to take your "biometrics" (fingerprints and so forth), interview you, and give you your certificate of naturalization at an oath ceremony. These things must happen in the United States. If you leave the United States after sending your citizenship application, you must come back to complete the application process.
Understanding these strangely overlapping requirements for naturalized U.S. citizenship is confusing for everyone, and consulting an experienced immigration attorney can be quite helpful.