Do I need a return or ongoing flight when I enter Thailand on a tourist visa?

When entering Thailand on a tourist visa, it is technically required to have proof of onward travel, such as a return flight ticket. While many travelers report that they have not been asked for this ticket by immigration, the requirement can depend on the airline’s policy. Some airlines may enforce this rule strictly, while others do not. Therefore, it is advisable to have an onward or return flight ticket, as failure to present one can lead to being denied boarding or entry into Thailand.