Most lawful permanent residents may apply for naturalization after five years of continuous residence. If you are married to and living with a U.S. citizen, you may qualify after three years. Continuous residence means you have maintained your primary home in the United States without long absences that disrupt eligibility. You must also meet physical presence requirements, meaning you were physically inside the United States for at least half of the required statutory period. Extended trips abroad may impact eligibility and should be carefully reviewed before filing.