Do I need a return ticket for my 90-day tourist visa in Thailand?

The need for a return ticket when booking travel to Thailand on a 60-day tourist visa (extendable to 90 days) varies depending on circumstances. Generally, airlines may require proof of onward travel, but it doesn't necessarily have to be a return ticket. Travelers can book a cheap or refundable ticket to another country (like Cambodia or Vietnam) to satisfy this requirement. Some have successfully traveled without producing a return ticket. It's also noted that a 60-day single entry visa can only be extended once for another 30 days.