United States visa guide: every main route explained

The B-2 visa covers tourism, holidays and visits to friends and relatives in the United States.

Medical treatment in the United States is a B-2 purpose.

The United States has no airside transit without immigration inspection, so travellers who are not visa-exempt need a C-1 transit visa or a B visa even to change planes; citizens of Visa Waiver Program countries can use ESTA.

The B-1 visa lets you visit the United States for business such as meetings, consultations with associates, conferences, contract negotiations and settling an estate, without taking a job or being paid from US sources.

Nationals of countries that have a treaty of commerce and navigation with the United States can obtain an E-2 visa to develop and direct a US business in which they have invested a substantial amount, or an E-1 visa for substantial trade between their country and the US.

Academic study at a US university, college, high school or English language programme requires an F-1 visa; vocational schools use M-1.

Academics and researchers invited by a US university, research institute or similar sponsor come on the J-1 professor or research scholar category.

Structured internships and professional training in the United States use the J-1 intern and trainee categories, arranged through a designated sponsor with a Training/Internship Placement Plan (DS-7002).

Au pairs live with a US host family for 12 months, provide child care and take academic courses, through a State Department-designated au pair sponsor.

H-1B lets US employers hire foreign professionals in specialty occupations that require at least a bachelor’s degree in a specific field.

L-1 lets multinational companies transfer employees from an office abroad to a related US office.

O-1A is for people with extraordinary ability in the sciences, education, business or athletics, and O-1B for extraordinary ability in the arts or achievement in film and television.

H-2A lets US farmers hire foreign workers for temporary or seasonal agricultural work, and H-2B covers temporary non-agricultural jobs such as hospitality and landscaping.

A US citizen can bring a fiancé(e) on a K-1 visa to marry within 90 days, or a spouse on an immigrant visa: CR-1 if married less than 2 years at admission (conditional 2-year green card) or IR-1 if married longer.

US citizens can petition for spouses, unmarried children under 21 and parents (if the citizen is 21 or over) as immediate relatives with no annual limit.

The EB-5 program gives conditional permanent residence to investors, with their spouse and unmarried children under 21, who invest $1,050,000, or $800,000 in a targeted employment area or infrastructure project, in a new commercial enterprise that creates at least 10 full-time US jobs.

A green card makes you a lawful permanent resident with the right to live and work anywhere in the United States.

ESTA is the online authorization that citizens of the 42 Visa Waiver Program countries need before visiting the United States for business, tourism or transit for up to 90 days.