Understanding US Citizenship and Immigration Services (USCIS): What You Need to Know in 2025

When people across the globe dream of living, working, or becoming citizens of the United States, one federal agency plays a central role in making that dream a reality: US Citizenship and Immigration Services (USCIS). Whether you're applying for a green card, seeking naturalization, petitioning for a family member, or requesting asylum, USCIS is the gatekeeper that evaluates your application, verifies your background, and ultimately decides your future in America.

In this in-depth guide, we will explore what USCIS is, how it operates, the services it provides, and how to navigate its processes effectively in 2025. Whether you're an immigrant, sponsor, employer, or legal professional, understanding how US Citizenship and Immigration Services works is critical for success in any immigration journey.

What Is US Citizenship and Immigration Services (USCIS)?

US Citizenship and Immigration Services (USCIS) is a component of the Department of Homeland Security (DHS). Established in 2003, USCIS replaced functions formerly handled by the Immigration and Naturalization Service (INS).

The primary mission of USCIS is to administer the nation’s immigration system efficiently and securely. It handles millions of immigration petitions and applications each year, ranging from temporary work visas to permanent residency and citizenship.

The Core Responsibilities of USCIS

USCIS is responsible for a wide range of immigration-related functions. These include:

1. Processing Immigration Petitions

USCIS reviews and adjudicates various immigration petitions, including:

• Family-based immigration (Form I-130)

• Employment-based petitions (Form I-140)

• Nonimmigrant visas (change or extension of status)

2. Green Card (Permanent Residency) Applications

USCIS oversees the application process for lawful permanent residence:

• Adjustment of Status (Form I-485)

• Removal of conditions on residence (Form I-751)

• Green card renewals and replacements

3. Naturalization and Citizenship

USCIS administers the pathway to U.S. citizenship for lawful permanent residents through:

• Naturalization (Form N-400)

• Certificate of Citizenship (Form N-600)

• Military naturalization

4. Asylum and Refugee Processing

USCIS handles initial asylum applications filed from within the U.S. and supports refugee resettlement programs.

5. Humanitarian Programs

USCIS offers various protections and reliefs, including:

• Temporary Protected Status (TPS)

• Deferred Action for Childhood Arrivals (DACA)

• VAWA petitions for abuse victims

• U visas for crime victims

• T visas for human trafficking survivors

6. E-Verify and Work Authorization

USCIS manages E-Verify, an electronic system for employers to confirm workers’ employment eligibility. It also issues Employment Authorization Documents (EADs).

7. Citizenship and Civic Integration

USCIS provides resources and support for new immigrants to learn English, understand U.S. history, and prepare for naturalization interviews.

USCIS Organizational Structure

USCIS operates under the Department of Homeland Security (DHS) and is headquartered in Washington, D.C.. It has regional service centers, district offices, application support centers (ASCs), and international offices (though many international offices have closed in recent years).

Here are key components of its structure:

• Field Offices: Handle interviews and local processing.

• Service Centers: Manage petition processing.

• Asylum Offices: Evaluate asylum claims.

• Administrative Appeals Office (AAO): Reviews appeals of certain denied petitions.

• Customer Service: Offers help via the USCIS Contact Center and online tools.

Popular USCIS Forms and What They’re Used For

Here’s a breakdown of some commonly used USCIS forms and their purposes:

Knowing which form to file and how to complete it correctly is crucial for success in any USCIS application process.

How to File with USCIS: Online vs. Paper

USCIS offers two main filing methods:

1. Online Filing

Many forms can now be filed online via the USCIS online account portal. Benefits include:

• Immediate confirmation of submission

• Real-time case updates

• Faster communication for RFEs (Requests for Evidence)

2. Paper Filing

Some forms still require physical submission to a USCIS lockbox or service center. Always check the form’s instructions and current mailing addresses before filing.

USCIS Processing Times and Case Status

How Long Does USCIS Take?

Processing times vary by form, location, and case complexity. Some petitions are completed within weeks, while others take months or years.

You can check estimated processing times at: