In general, the B Visa allows individuals to visit the US temporarily for business (B-1 Business Visitor) or for pleasure (B-2 Tourist Visa). Nationals of certain countries can also visit the US temporarily without a visa if they qualify for the Visa Waiver Program (VWP).
The B-1 Business Visa enables business visitors to engage in business activities such as meetings or conferences. However, the B-1 Business Visa is not for meaningful work or employment in the United States.
In the context of the B-1 Business Visa, “Business Activities” refers to conventions, conferences, consultations and other legitimate activities of a commercial or professional nature. These would not include local employment or labor for hire.
Honoraria Payments: B-1 Business Visa holders who engage in activities at certain higher educational institutions, related nonprofit organizations, or nonprofit or governmental research organizations are eligible to receive honoraria payments and incidental expenses for usual academic activities lasting no more than 9 days at any single such institution or organization. More information on B-1 Visa Honoraria.
The B-2 Tourist Visa enables foreign nationals to travel temporarily in the US. Such trips cannot involve employment. Your length of stay may be up to one year. B visa holders may change or extend their status to other categories. But remember that the B visa requires intent to remain in the US only temporarily. So take care when trying to amend or extend your stay to avoid violating the terms of the B visa.
Note that nationals of countries participating in the Visa Waiver Program (VWP) may enter the US without a visa and stay for a period of up to 90 days.
You must depart the US on/before the date on your admission stamp or I-94 unless USCIS approves a request to extend your stay.
Failure to depart the US on time will result in you being out of status. US law automatically voids visas of travelers who are out of status. Multiple-entry visas that become void are no longer valid for future US entries. Overstays may also become ineligible for US visas in the future. See Visa Denials and Ineligibilities and Waivers: Laws.
Individuals who enter under the Visa Waiver Program may not change or extend status while in the US. Rather, they must leave the US, and visit a US consulate to obtain a visa.