After obtaining permanent resident status (a green card), a person may wish to become a U.S. citizen by naturalization.  The process to apply for U.S. citizenship is called naturalization (N-400 Form). American law regulates the procedure and eligibility for naturalization.

General Naturalization Criteria

First, to apply for citizenship, a person must satisfy general requirements:

• age 18 or older,
• lawful admission as a U.S. permanent resident,
• continuous residence in the U.S. for at least five years after obtaining permanent resident status,
• physical presence in the U.S. for at least 30 months within the 5 years period before filing the naturalization application,
• 3 months residence in a state or USCIS district exercising jurisdiction over the applicant’s residential location,
• continuous residence in the U.S. from the N-400 filing date until the date USCIS admits the applicant into citizenship,
• demonstrate good moral character, attachment to U.S. constitutional principles, and support the United States’ good order and happiness, and
• did not desert the U.S. Armed Forces or depart the United States to avoid military service.   

See 8 C.F.R. § 316.2(a).

Can a Permanent Resident Apply for Citizenship Based upon Marriage to a U.S. Citizen?

Yes. A permanent resident, who is married to a U.S. citizen, may apply for U.S. citizenship by naturalization. For marriage-based naturalization, the permanent resident must satisfy the above criteria with a few exceptions. For example, applicants must prove marital union with the U.S. citizen spouse for 3 years before the N-400 exam. Applicants only need to continuously reside in the U.S. for 3 years after obtaining a green card and show physical presence for 18 months. If the U.S. citizen spouse naturalized in the past, that spouse must have citizenship for 3 years before the applicant’s N-400 exam. If difficulties arose during the marriage, applicants should apply caution as American law carefully defines marital union for naturalization purposes.    

Physical Presence Exception for Applicants Married to U.S. Military Personnel

American law provides an exception to the physical presence requirement for permanent residents married to a U.S. citizen serving in the U.S. Armed Forces. For example, USCIS will consider an N-400 applicant’s time living abroad with a U.S. citizen as physical presence if the applicant was married to the military member. Also, the N-400 applicant must demonstrate that official orders authorized residing abroad with the U.S. citizen, and the applicant resided in marital union with the military member. Importantly, U.S. law defines “marital union” for marriage-based naturalization purposes. See 8 C.F.R. § 319.1(b).