美国给与世界各国经商/旅游签证的有效期对比图

The two types of B visa are the B-1 visa, issued to those seeking entry for business purposes, and the B-2 visa, issued to those seeking entry for tourism or other non-business purposes. In practice, the two visa categories are usually combined together and issued as a "B1/B2 visa" valid for a temporary visit for either business or pleasure, or a combination of the two. Visitors from some countries do not need to obtain a visa for these purposes

 

US visa validity period

  United States

  120 months

  60 months

  24-48 months

  12 months

  Under 12 months