The H1B visa is a non-immigrant US visa, governed by the Immigration & Nationality Act, section 101(a) (15) (H). This type of visa allows US employers to hire contractual foreign workers in specialty occupations. H-1B holders can work only for the petitioning US employer and must not engage in activities that are not indicated in the original petition. However, sponsoring employers may allow H1B holders to work with a different employer, provided that certain legal requirements are met.

H1B or specialty occupation visas are available to skilled workers who have attained the equivalent of a US college or university education or relevant training. Emigrants or those educated outside the USA are required to have a relevant or partly relevant degree, plus three or more years of work experience in the target position. For anyone seeking to practice their profession, such as medicine, law or accountancy, a relevant state or federal licence is required.

The dependents of aliens holding a US work visa are prohibited from working in the USA unless they qualify for a work visa in their own right and have a US employer that will sponsor them. Nevertheless, dependents of the US visa holder may study in the country. They must obtain their derivative visas at the same time as the principal US visa holder.

H1B visa holders can remain in the USA for three years, though the duration of stay can be extended to six. Despite this limit, H1B visa holders are not required to stay for a specific period in the job, which they originally sought when they applied for visa.