Foreign spouses of U.S. green card holders (people with lawful permanent residence) are eligible for immigration to the U.S., under the family second preference category (2A). (See I.N.A. Section 203(a)) This is true for both same-sex and opposite-sex couples, so long as the marriage is legally recognized in the state or country where it took place.
Unfortunately, the foreign-born spouse's eligibility will not lead to an immigrant visa (the equivalent of a green card) right away. The process can take several years, as described below. But the U.S. green card holder may be able to speed things up by becoming a U.S. citizen, as also described below.
The number of immigrant visas issued each year under the family second preference is limited to approximately 114,200, plus some unused visas from other categories. This allotment is not for spouses alone: Category 2A also covers unmarried children of lawful permanent residents.
As a result, there are never enough visas to give to the number of people who apply for them each year, and a long waiting list has developed. A spouse’s place on the waiting list depends on his or her "priority date," which is set by the date that the U.S. resident files the initial I-130 petition on the foreign-born spouse’s behalf (on Form I-130, issued by U.S. Citizenship and Immigration Services or USCIS).
To see the priority dates of people who are currently receiving visas, and ultimately track one's own place on that list, view the Visa Bulletin on the U.S. State Department’s website. Typical waits are four or five years long.
In order for a foreign-born spouse to be eligible for a green card based on marriage, the marriage must, first off, be legally valid (which you'll need to prove with a government-issued marriage certificate) and also be bona fide; that is, not have been entered into merely for the purpose of evading immigration laws. You’ll be asked to prove that the marriage is bona fide at various points to the application process.
In addition, the foreign-born spouse must not be "inadmissible" to the United States. The grounds of inadmissibility are long and complicated, but the most troublesome ones for married couples tend to be those concerning past crimes or immigration violations and the likelihood that the immigrant will become a “public charge” because the couple’s household finances are not sufficient to avoid receiving need-based government assistance.
A particularly difficult ground of inadmissibility arises if the foreign-born spouse is living illegally in the United States, whether that's due to having entered without inspection or having overstayed a visa.
First, understand that starting a green card application process on someone's behalf (that is, filing Form 1-130 and placing the spouse on the waiting list) will not give the person any right to come to or remain in the United States. Unless a spouse already has a valid visa (and hasn't stayed past the required departure date) or some other right to be in the United States, the spouse is expected to wait in his or her home country until the priority date is current before moving forward to claim any immigration rights.
Waiting in the United States illegally until a priority date becomes current can lead to disastrous results. That’s because accruing unlawful presence in the United States can lead to an inadmissibility bar of several years. With 180 days of unlawful presence, the spouse can (usually after leaving the U.S. for the visa interview at a U.S. consulate abroad) be barred from returning to the U.S. for three years; and with one year’s unlawful presence, the time bar becomes ten years.
But applying through a U.S. consulate is likely to be the immigrating spouse's only choice for applying for the immigrant visa/green card. Someone whose U.S. spouse is a permanent resident or who has been living illegally in the United States is unlikely to be able to "adjust status," that is apply for a green card without leaving the United States. But if the U.S. spouse becomes a U.S. citizen, it improves the situation considerably, as discussed below. See an experienced immigration attorney if you are attempting to obtain a green card for someone already living illegally in the United States.
After the I-130 has been approved by USCIS, and the spouse’s priority date has become current, you’ll receive further forms and instructions from the National Visa Center (NVC) and then the appropriate U.S. consulate in the immigrant’s home country.
Or, in the rare case that the foreign-born spouse is in the United States and eligible to adjust status here, you will need to prepare a packet of forms (starting with Form I-485) and documents, and submit these by mail to USCIS.
The final step in this process is for the foreign-born spouse to attend an interview at a U.S. consulate, where the paperwork will be reviewed and a decision made on the immigrant visa. Upon entry to the U.S. with the immigrant visa, the immigrant spouse becomes a lawful permanent resident.
Or, if the spouse will be adjusting status, the two of you will attend an interview at a local USCIS office.
Once the green card holder naturalizes to U.S. citizenship (which he or she can probably apply for after five years of permanent residence), the foreign-born spouse becomes what's known as an "immediate relative." That means the person is not subject to the waiting list, but can move forward with a green card application right away.
As a further benefit of being an immediate relative, if the foreign-born spouse in in the United States after a legal entry (such as with a visa, used for its original purpose and without any secret intent of marrying), he or she can go ahead and apply to adjust status, regardless of any overstay.
Unfortunately, people who entered the U.S. without inspection or illegally receive no such benefit. But they may be able to apply for a waiver of the inadmissibility that results from spending excessive time in the U.S. unlawfully.
In fact, something called the "provisional" or "stateside" waiver allows immigrants who are not inadmissible for any reason other than unlawful presence to apply to USCIS for the waiver of inadmissibility before leaving the U.S. for their consular interview. That way, they can be fairly certain that the immigrant visa will be granted and be allowed to return to the U.S. soon. See Staying in the U.S. With the I-601A Provisional Waiver of Inadmissibility and Tips for Filing an I-601A Provisional Waiver Application.
If the foreign-born spouse is living overseas while awaiting a current priority date, you'll need to advise the National Visa Center, which is holding the file waiting for the old priority date to become current, of the petitioner's change in status to U.S. citizen. The easiest way to do so is to contact the NVC online. It will request a copy of the naturalization certificate then forward the file to the appropriate consulate for immigrant visa processing.
The above is a brief summary of a complicated process and set of laws. For a detailed personal analysis of a foreign-born spouse’s eligibility for a green card, and help with the application process, talk to an experienced U.S. immigration attorney.