With certain exceptions, applicants must be at least 18 years old.
An applicant must have been lawfully admitted to the United States for permanent residence. Lawfully admitted for permanent residence means having been legally accorded the privilege of residing permanently in the United States as an immigrant in accordance with the immigration laws.
An applicant is eligible to file if, immediately preceding the filing of the application, he or she:
1. Has been lawfully admitted for permanent residence (see preceding section);
2. Has resided continuously as a lawful permanent resident in the United States for at least five years prior to filing with no single absence from the United States of more than one year;
3. Has been physically present in the United States for at least 30 months out of the previous five years;
4. Has resided within a state or district for at least three months.
Generally, an applicant must show that he or she has been a person of good moral character for the statutory period (typically five years, but three years for an applicant married to a U.S. citizen or one year for an applicant serving in the U.S. Armed Forces) prior to filing for naturalization. An applicant is permanently barred from naturalization if he or she has ever been convicted of murder or aggravated felony. A person also cannot be found to be a person of good moral character if during the past five years he or she has been convicted of a number of other crimes.
An applicant must show that he or she is attached to the principles of the Constitution of the United States.
With certain exceptions, applicants for naturalization must be able to read, write, speak, and understand words in ordinary usage in the English language.
With certain exceptions, an applicant for naturalization must demonstrate a knowledge and understanding of the fundamentals of the history and of the principles and form of government of the United States.
To become a citizen, one must take the oath of allegiance. By doing so, an applicant swears to:
1. Support the Constitution and obey the laws of the United States;
2. Renounce any foreign allegiance and/or foreign title;
3. Bear arms for the Armed Forces of the United States or perform services for the government of the United States when required.