U.S. citizens who have a valid passport are not required to obtain a visa in order to enter Thailand. Travelers coming from the United States, UK or the EU all benefit from the visa exemption rule. This allows tourists from 55 countries who arrive via land or air, a 30-day stay in Thailand. This visa-free travel is easily extendable if tourists are planning a longer stay. Instead of a visa, travelers will need a passport that is valid for at least another 6 months. ASEAN passport holders are also granted a 30-day stay, but not always eligible for an extension. If you wish to go on an extended trip, you can apply for a 60-day tourist visa in any Thai embassy. Generally, the tourist visa must be obtained before arriving in Thailand and must be used within 90 days from the date of issue.