Under the US immigration rules, foreign nationals planning to travel to the US, either to stay on a temporary basis or to settle permanently, have to hold appropriate permission to seek permission for entry at the border. This usually requires the individual to apply for a US visa.

The main body of legislation governing US immigration is the Immigration and Naturalization Act (INA). The immigration rules are then implemented through a system of routes and programs designed to achieve the following aims:

 

• To reunify families through family-based immigration.
• To admit non-US nationals who have valuable skills through economic immigration.
• To provide protection to refugees and asylum seekers through humanitarian relief routes.
• To promote diversity across the nation through the Diversity Visa Program.

 

US immigration rules are, however, complex and subject to change in line with the prevailing political mandate and environmental circumstances.

In this guide, we summarize the key tenets of the system and what they mean for foreign nationals traveling to the US.

 

US Immigration Rules Overview

 

Foreign nationals seeking to enter the United States must meet a wide range of immigration requirements depending on their purpose of travel, intended length of stay and visa classification. US immigration law is structured around various visa categories, each with specific criteria that applicants must satisfy to be eligible for entry.

The most basic distinction in US immigration rules is between immigrant and nonimmigrant visas. Immigrant visas are intended for individuals seeking permanent residence in the US, while nonimmigrant visas are for those entering temporarily, such as for tourism, business, work, or study.

For nonimmigrant visas, travelers must demonstrate that their stay will be temporary and that they plan to return to their home country once their permitted period in the US ends. Applicants must show ties to their home country—such as a job, property, or family—that suggest they do not intend to overstay. Most nonimmigrant visas, such as B-1 (business), B-2 (tourism), or F-1 (student), require the applicant to complete Form DS-160 and attend an interview at a US embassy or consulate. A valid passport, photo and proof of the purpose of travel are also required.

Some visa categories have more specific standards. For example, employment-based visas often require a job offer from a US employer and, in many cases, a labor certification from the Department of Labor. The H-1B visa, for specialty occupations, requires a bachelor’s degree or equivalent in a specific field. The O-1 visa, for individuals with extraordinary ability in areas such as the arts or sciences, demands extensive documentation of achievement. Investors applying under the E-2 or EB-5 programs must provide evidence of the funds being invested and the legitimacy of the business venture.

Family-based immigrant visas require a US citizen or lawful permanent resident sponsor to file a petition on behalf of the applicant. The petitioner must also meet financial requirements, typically through an Affidavit of Support, to show that the applicant will not become reliant on public benefits. Eligibility depends on the relationship—spouses, children, siblings, and parents may qualify under different categories. Wait times vary depending on the family category and the applicant’s country of origin.

Applicants for green cards must also show that they are admissible to the United States under immigration law. Grounds for inadmissibility include certain criminal convictions, immigration violations, and health-related issues. In some cases, a waiver may be available.

Those applying for any US visa must be prepared to provide accurate and complete information. Misrepresentation can lead to denial or permanent ineligibility. Supporting documents must clearly explain the applicant’s background, intentions, and qualifications. Every visa decision is ultimately made at the discretion of a US consular officer or immigration official based on the evidence provided.

While requirements vary widely by visa type, all travelers must be prepared to meet the legal standards for their intended immigration pathway. Careful preparation and a clear understanding of eligibility rules are essential for a successful application.

 

Source of Law	Type	Description
Immigration and Nationality Act (INA)	Statute	The primary body of law governing immigration and citizenship in the United States.
Code of Federal Regulations (CFR)	Regulations	Implements the INA through detailed rules published by federal agencies, especially Title 8 (Aliens and Nationality) and Title 22 (Foreign Relations).
Department of Homeland Security (DHS) Policy	Agency Guidance	Includes internal policies and memoranda used by USCIS, CBP, and ICE to interpret and apply immigration law.
Board of Immigration Appeals (BIA) Decisions	Administrative Case Law	Binding decisions on immigration judges and DHS unless overruled by federal courts.
Federal Court Decisions	Judicial Precedent	Interpret immigration law and resolve legal challenges, including from the Supreme Court and circuit courts of appeal.
US Constitution	Foundational Law	Provides the federal government with authority over immigration and limits actions through due process and equal protection rights.
Presidential Proclamations and Executive Orders	Executive Action	Used by presidents to manage border policy, refugee admissions, and temporary entry restrictions.

 

US immigration under the Trump 2.0 Administration

 

Under the Trump 2.0 presidency, US immigration policy has entered a tougher, more tightly controlled era. Application processing is slower. Scrutiny is sharper. Bureaucratic hurdles are higher. From visa interviews to supporting documentation, nothing is getting waved through. But while the rhetoric may sound like the gates are closing, the reality is more nuanced. The United States is not shutting its doors, but it is tightening the bolts on the frame.

For those who meet the criteria, follow the rules and are prepared to engage with a more demanding process, the US remains one of the most rewarding destinations for work, study, investment and long-term opportunity. Whether you’re a skilled professional, a global entrepreneur or a family member seeking to reunite with loved ones, legal immigration routes remain in place, albeit with far less margin for error.

In an environment shaped by policy shifts, procedural slowdowns and increased enforcement, success now requires precision, patience and documentation that leaves no room for doubt. The message from Washington is clear: comply and you’re welcome. Cut corners and you’ll be cut out. So the system hasn’t closed, it’s simply expecting more from those who want in.

Visa Waiver Program

 

Foreign nationals from Visa Waiver countries may be eligible to travel to the US through the Visa Waiver Program instead of obtaining a visa, under the following conditions:

 

• You are a national of a Visa Waiver country.
• You hold ESTA authorization.
• You will travel by a US approved air or sea carrier.
• Your visit is for the purposes of tourism, short-term medical treatment or business, in keeping with a B1, B2 or B1/B2 visa.
• Your visit will last no more than 90 days.
• You hold a valid e-passport.

 

Temporary, nonimmigrant visas

 

The US permits admission of qualifying non-US nationals citizens on a temporary basis under the nonimmigrant visa scheme.

Nonimmigrant visas generally fall into one of the following categories, each with their own specific eligibility and application requirements. Given the time-limited duration of a nonimmigrant visa, applicants in most cases will need to satisfy the adjudicating officer of their intention to leave the US by the date of visa expiry. This would usually involve evidencing through documentation ‘sufficient ties’ to their country of residence.

 

Tourism and short-term medical treatment

 

The B2 visa allows a foreign national to visit the US for the purposes of tourism or short-term medical treatment.

Tourism activities covered by a B2 visa include:

• taking a holiday in the US
• visiting family and friends who live in the US
• unpaid participation in an amateur event, such as a sports contest
• attending a short study course that does not lead to a qualification

A B2 visa may also be used to visit the US for medical treatment which can be completed within 90 days. Further conditions relating to the use of a B2 visa for medical treatment include:

• A person suffering from certain contagious diseases will not be granted a visa.
• In the case of organ donation, you must provide evidence that you are a suitable donor.
• The treatment must not be available in your home country.
• You must provide a letter from your doctor, outlining your medical condition and treatment.
• You must provide evidence of acceptance from the US doctor or establishment who will provide the medical treatment.
• You must prove that you can afford any costs incurred during your time in the US.

 

Business visits

 

The B1 visa allows a foreign national to visit the US on a temporary basis for business purposes.

Business activities covered include:

• attending business meetings, conventions or conferences
• negotiating a contract with a customer
• installing or repairing machinery
• speaking engagements at a US university for 9 days or less
• visiting prospective business premises in the US
• taking part in a voluntary service programme which benefits a US local community

The B1 visa can’t be used for employment purposes.

 

Combination B1/B2 visa

 

In practice, overseas Consulates and Embassies processing US visitor visas will typically issue the B1/B2 combination visa, since this permits the holder to carry out permissible activities relating to business and tourism during the period of stay.

 

Temporary employment

 

If you intend to take up temporary employment in the US, it will be necessary to obtain the relevant temporary worker visa.

The temporary worker visa is appropriate for employment that is short-term and is lasts for a definite or fixed amount of time.

This category covers:

 

• H-1B – person in speciality occupation
• H-1B1 – free trade agreement professional, for example, from Chile or Singapore
• H-2A – temporary agricultural worker
• H-2B – temporary non-agricultural worker
• H-3 – trainee or special education visitor
• L-1 – intracompany transferee
• O-1 – person with extraordinary ability or achievement
• P-1 – member of an entertainment group or an individual/team athlete
• P-2 – artist or individual/group entertainer under a reciprocal exchange program
• P-3 – artist or individual/group entertainer performing, teaching or coaching under a program of performance or presentation
• Q-1 – person taking part in an international cultural exchange program

 

Each of the above visas require that the related US employer files a petition with USCIS.

Members of the foreign press and media visiting the US for work purposes should apply for an I visa.

The R visa is suitable for a foreign national who wishes to visit the US to work in a religious capacity on a short-term basis.

 

Treaty Trader or Treaty Investor

 

The E1 Treaty Trader visa is used by foreign nationals who wish to carry out substantial trade between the US and a trading firm in their home country.

The E2 Treaty Investor visa is used by entrepreneurs and business owners wishing to operate a business in the US, through setting up a new enterprise or investing in an existing US business.

Any person seeking an E1 or E2 visa must be a national of, or their employing business must bear the nationality of, a country which has a treaty of commerce and navigation with the US.

 

Study and exchange

 

This category covers F1, M1 and J1 visas.

To study in the US, you must hold the relevant student visa.

The F1 visa covers:

• university or college
• high school
• private elementary school
• seminary
• conservatory
• any other academic institution,

The M1 visa is appropriate for vocational studies and to attend a non-academic institution.

Where a student wishes to visit the US to participate in an exchange programme, they must hold a J1 visa.

 

Diplomats and other government officials

 

Foreign diplomats and other government officials visiting the US on behalf of their country’s government must use either an A1 or A2 visa.

The A1 visa is appropriate for a head of state, government minster or European Union delegation representative. The A2 visa is suitable for full-time government employees, foreign military members stationed at a US military base, or the staff of a European Union delegation representative.

 

Immigrant visas

 

Lawful permanent residency (i.e. Green Card status) allows a foreign national to work and live lawfully and permanently in the United States. Lawful permanent residents (LPRs) are eligible to apply for nearly all jobs (i.e., jobs not legitimately restricted to U.S. citizens) and can remain in the country even if they are unemployed.

The INA stipulates an annual worldwide limit of 675,000 permanent immigrants, with certain exceptions for close family members.

US immigration laws require any foreign national seeking an immigrant visa to be sponsored by an employer, a family member who is already a US citizen, or a US lawful permanent resident.

Immigrant visas fall into the following categories:

 

Category	Description
Family	– Spouse, unmarried child under 21, or parent of a US citizen – Spouse, unmarried child under 21, or unmarried son/daughter of a US lawful permanent resident – Son/daughter over 21 or sibling of a US citizen
Fiancé or Fiancée	Engaged to a US citizen
Employment	First preference: Individuals with extraordinary ability, outstanding professors and researchers, certain multinational executives and managers Second preference: Professionals and individuals with exceptional ability in the sciences, arts, or business Third preference: Professionals, skilled workers, and unskilled workers in demand Fourth preference: Certain special immigrants Fifth preference: Immigrant investors
Special Immigrants	– Iraqi or Afghan translators and interpreters – Iraqis or Afghans employed by or on behalf of the US government – Religious workers
Returning Resident	US lawful permanent or conditional resident returning after more than one year (or two years with a re-entry permit)
Diversity Visa Lottery	Limited number of immigrant visas available to nationals of countries with historically low immigration to the US

 

Becoming a US citizen

 

Once you have held the status of US lawful permanent resident for 5 years, with continuous residence for those 5 years with no time spent abroad for 6 months or longer, you may be eligible to apply for US citizenship.

This will depend on factors such as:

 

• being at least 18 years old
• having a good moral character
• having a good level of English and civics knowledge
• a willingness to form an attachment with the US constitution
• and other factors relating to your personal circumstances

 

Need assistance?

 

Applications across all classifications face considerable adjudication scrutiny. This demands travellers ensure any application is completed thoroughly with comprehensive supporting documents, and that potential issues of inadmissibility are fully considered.

As specialists in US immigration, NNU’s attorneys can advise on all aspects of US entry requirements. Contact us for advice on eligibility and the relevant application process to be followed for travel to the US.

 

Glossary

 

Term	Definition
Adjustment of Status	The process of applying for permanent residency from within the US without returning to one’s home country.
Affidavit of Support	A document in which a sponsor agrees to financially support a visa applicant if necessary.
Conditional Resident	A person granted permanent resident status on a conditional basis, typically based on a recent marriage.
Diversity Visa Lottery	An annual program offering immigrant visas to individuals from countries with low rates of immigration to the US.
Employment-Based Visa	A category of visa for individuals who qualify for permanent residence through a qualifying job or job offer in the US.
Fiancé Visa (K-1)	A visa that allows a foreign national engaged to a US citizen to enter the country for marriage within 90 days of arrival.
Form I-130	The petition used by a US citizen or permanent resident to sponsor a qualifying family member for a green card.
Green Card	The common term for a US Permanent Resident Card, which grants authorization to live and work permanently in the US.
Lawful Permanent Resident (LPR)	A noncitizen who is legally authorized to live and work in the US on a permanent basis.
Priority Date	The date a green card petition is filed, used to determine visa availability in preference categories.