Naturalization: Policy Overview and Selected Trends

Naturalization: Policy Overview and Selected Trends

Naturalization: Policy Overview and Selected Trends

Updated September 16, 2025 (IF12322)

Naturalization is the voluntary process by which a foreign national becomes a U.S. citizen. In 2024, approximately 26 million naturalized U.S. citizens were residing in the United States, representing about 51% of the total foreign-born population.

U.S. citizenship affords certain rights, benefits, and eligibility; including eligibility for a U.S. passport, the right to vote and run for elected office, eligibility for certain civil service and law enforcement jobs, and protection from deportation. In addition, under the Immigration and Nationality Act's (INA's) family-based immigration system, U.S. citizens may sponsor a broader range of family members to immigrate than lawful permanent residents (LPRs). LPRs are foreign nationals authorized to live permanently in the United States. Unlike the relatives of LPRs, the immediate relatives of U.S. citizens (spouses and unmarried minor children, and parents of adult U.S. citizens) are not subject to numerical limits.

Requirements for naturalization are enumerated in the INA. Generally, in order to naturalize, a foreign national must be an LPR, meet certain U.S. residence and physical presence requirements, demonstrate English language ability and knowledge of U.S. history and civics, have good moral character, and show attachment to the principles of the U.S. Constitution. Individuals must be at least 18 to naturalize; children derive citizenship through their parents. U.S. Citizenship and Immigration Services (USCIS), a Department of Homeland Security (DHS) agency, adjudicates naturalization applications.

Eligibility Requirements

U.S. Residence and Physical Presence

Generally, an LPR becomes eligible to naturalize after five years of continuous U.S. residence. During at least half that time (30 months), the individual must have been physically present in the United States. LPRs who have been married to a U.S. citizen for at least three years may naturalize after three years of U.S. residence and 18 months of physical presence.

The INA contains special provisions for the naturalization of noncitizen members of the U.S. Armed Forces. Those who apply while in service or within six months of discharge are exempt from residence and physical presence requirements. Those who serve during designated periods of military hostilities may naturalize without having first been an LPR.

Good Moral Character

Naturalization applicants must demonstrate that they have been persons of good moral character (GMC). GMC is determined on a case-by-case basis by USCIS based on the totality of the circumstances, considering factors such as community involvement, employment history, and absence or presence of criminal history. The INA and Code of Federal Regulations contain certain bars to establishing GMC (e.g., conviction of certain crimes).

In August 2025, USCIS issued a policy memorandum directing USCIS officers to "account for an alien's positive attributes and not simply the absence of misconduct" for GMC determinations. Officers are to place a "greater emphasis on positive attributes or contributions," such as community involvement/contributions, family caregiving/ties, education, employment, length of residence, and compliance with tax obligations. The guidance advises "greater scrutiny of disqualifying behavior and action," including bars to GMC and other acts (e.g., habitual traffic infractions). USCIS is to also consider evidence of "genuine rehabilitation" of wrongdoing, such as payment of overdue child support or taxes.

English and Civics Knowledge

Naturalization applicants must demonstrate an ability to read, write, and speak English and take a civics exam that demonstrates understanding of U.S. history and government. Individuals aged 50 and older with qualifying U.S. residence may be eligible for modifications to these requirements. In addition, individuals who are unable to comply with these requirements because of a physical or developmental disability or mental impairment are exempt.

Process

Individuals apply to naturalize by filing an Application for Naturalization (Form N-400) with USCIS with required fees (currently $760 for paper filing or $710 for online filing). Reduced fees and fee waivers are available to certain applicants. Those qualifying based on military service do not pay a fee.

Next, applicants undergo biometric screening, during which USCIS collects an applicant's fingerprints, photograph, and signature. In a departure from USCIS policy since 1991, in August 2025, USCIS announced it would exercise its statutory authority to conduct personal investigations of naturalization applicants, known as "neighborhood investigations," for which it may request "testimonial letters from neighbors, employers, co-workers, and business associates."

Applicants must complete an interview with a USCIS officer in which they answer questions about their application and background and complete their civics and English tests. Those who pass their interviews and exams become U.S. citizens after taking the Oath of Allegiance in a public ceremony. The Oath may be administered by USCIS in an administrative ceremony or by a federal judge in a judicial ceremony.

Dual Citizenship, Expatriation, and Revocation

An individual who naturalizes in the United States may retain the citizenship of another country if that country permits it. The United States does not officially recognize dual nationality, but it has no authority to prohibit another country from continuing to treat an individual as its citizen.

A naturalized citizen may have his or her citizenship revoked in federal court (revocation, commonly referred to as "denaturalization") on the basis that he or she procured citizenship illegally by concealment of material facts or by willful misrepresentation. Naturalized citizens who become members of or affiliated with the Communist party or other totalitarian parties or terrorist organizations within five years of naturalization are also subject to revocation. In June 2025, the U.S. Department of Justice issued a memo identifying denaturalization proceedings as an enforcement priority "in all cases permitted by law and supported by the evidence."

A native-born or naturalized U.S. citizen may voluntarily lose their citizenship by committing certain expatriating acts if those acts are committed with the intention of relinquishing U.S. citizenship. These include voluntary naturalization in a foreign country after age 18, making a formal declaration of allegiance to a foreign country after age 18, serving in the armed forces of a foreign country engaged in hostilities against the United States, and serving in the armed forces of a foreign country as an officer. An individual may also voluntarily renounce their U.S. citizenship before a U.S. diplomatic or consular officer abroad (e.g., because the individual wishes to run for elected office in another country).

Naturalization Trends

Annual Naturalizations

On average, during the last 20 years, approximately 758,000 individuals naturalized annually, with naturalizations ranging from 604,000 in FY2005 to 1,047,000 million in 2008 (Figure 1).

Figure 1. Annual Naturalizations, FY2005-FY2024

Source: FY2005-FY2023: DHS, 2023 Yearbook of Immigration Statistics; FY2024: USCIS, "Fiscal Year 2024 Naturalization Statistics."

In FY2024, approximately 818,500 persons naturalized.

Application Processing

In recent years, USCIS has reduced its processing times for naturalization applications following processing backlogs in previous years. A 2021 executive order directed federal agencies to develop a plan to "substantially reduce current naturalization processing times." That fiscal year, the median processing time for the N-400 was 11.5 months. In 2022, USCIS announced new efforts to reduce processing times for the N-400, with a goal to process them within 6 months. The median processing time for the N-400 was 5.5 months in the first nine months of FY2025. As of March 31, 2025, approximately 536,000 naturalization applications were pending with USCIS.

Origins of Naturalized Citizens

From FY2014-FY2023, the largest proportion of individuals who naturalized were from Asia and North America (including Mexico, the Caribbean, and Central America), each representing more than one-third of those naturalized (Figure 2). Individuals born in Africa and Europe each represented approximately 10%, followed by South America (9%) and Oceania (<1%). The top 10 countries of origin for naturalizations during that period, listed from highest to lowest, were Mexico, India, the Philippines, Cuba, China, the Dominican Republic, Vietnam, El Salvador, Jamaica, and Colombia, cumulatively representing about half of all naturalizations.

Figure 2. Naturalized Citizens by Region of Origin

Source: DHS, 2023 Yearbook of Immigration Statistics.

Eligible to Naturalize

DHS's Office of Homeland Security Statistics estimates that as of January 2023, 9 million LPRs were eligible to naturalize, based on meeting age and residency requirements, representing approximately 71% of the 12.7 million LPRs residing in the United States. Nearly half of those eligible to naturalize were from North America, with about a quarter from Mexico.

Additional Information

For more information, see the following:

CRS Infographic IG10028, Naturalization: The Process of Becoming a U.S. Citizen

CRS Report R43366, U.S. Naturalization Policy