Do I need a passport or visa to enter?
If you are a U.S. citizen tourist staying for fewer than 30 days, you do not require a visa, but your passport must be valid for at least six months beyond the date of your entry into Thailand. Thai Immigration officials may ask for your onward/return ticket, and airlines may ask for this information when you book or check in. The U.S. Embassy and Consulate are not able to intervene with Thai Immigration or the airlines regarding their regulations and policies. If you are a tourist entering Thailand by air without a visa, you are allowed to stay in Thailand for 30 days per visit. If you are a tourist entering Thailand by land without a visa, you are allowed to stay in Thailand for 15 days per visit. Business travelers should check with a Royal Thai Embassy about visa requirements. You must pay a Passenger Service Charge in Thai baht (Thai currency) when you depart from any of Thailand's international airports; this charge is included in the ticket price for flights from Bangkok's main airport, Suvarnabhumi International.
When you enter the country, Thai Immigration officials stamp your passport with the date your authorized stay will expire. If you remain in Thailand beyond this date without getting an official extension, Thai Immigration officials will fine you 500 baht per day, up to a maximum of 20,000 baht (approximately $690 at baht 29:$1.00) when you leave Thailand. Make sure your passport is stamped with the date your authorized stay will expire before you leave the Immigration counter. Replacing a missing stamp later often requires a trip back to your original port of entry. If the police find that you are out of legal status before you leave the country (for example, during a Thai Immigration "sweep" through a guesthouse or in a popular a tourist area), you will be jailed, fined, and deported at your own expense, and you may also be barred from re-entering Thailand. These determinations are the legal responsibility of the Royal Thai government, and the U.S. Embassy or Consulate may not intervene in the application of Thai law. Private "visa extension services," even those advertising in major periodicals or located close to Immigration offices or police stations, are illegal. A number of U.S. citizens are arrested at border crossings each year with counterfeit visas and entry stamps they have obtained through these illegal services.
It is illegal for foreigners to work in Thailand without a work permit. This includes unpaid work, volunteer work (even for charitable causes), and work in exchange for room and board. If you work in Thailand without a work permit, you are subject to arrest, jail time, a fine, and deportation. Before traveling to Thailand for work -- whether or not you will receive compensation -- you should check with the Royal Thai Embassy to ensure that your plans are consistent with Thai law. Several U.S. citizens are arrested each year due to work permit violations.
Thailand's entry/exit information is subject to change without notice. For further information on Thailand's entry/exit requirements, contact the Royal Thai Embassy, 1024 Wisconsin Avenue, N.W., Washington, D.C., 20007, telephone (202) 944-3600, or contact the Thai consulates in Chicago, Los Angeles, or New York City. The Ministry of Foreign Affairs website lists Thai embassies and consulates worldwide and provides current information about Thailand, including visa and other polices. The Royal Thai Police Immigration Bureau maintains an English-language website as well.