Foreigners who entered the country with any visas Thailand It is not permitted to work until they get the work permit. Foreigners who wish to work in the country, Thailand will need to obtain an immigrant Visa category is a valid Non-Immigrant "B" so that it can apply to obtain a work permit. Information about obtaining a work permit is available at the Web site of the Department of employment. Ministry of labour www.doe.go.th/workpermit/index.html