Be at least 18 years of age at the time you file the application. Have been a lawful permanent resident for the past five years, or three years if you are married to a U.S. citizen and you have been living with your spouse for at least three years prior to filing. Have continuous residence and physical presence in the United States. Be able to read, write, and speak basic English. Demonstrate good moral character. Demonstrate a knowledge and understanding of U.S. history and government. Demonstrate a loyalty to the principles of the U.S. Constitution. Be willing to take the Oath of Allegiance. The Citizenship Assistance Portal will help explain each of these requirements to determine your eligibility.