Do I need to show an onward ticket with a Non-Immigrant O visa upon entering Thailand?

Most recent experiences suggest that travelers entering Thailand with a Non-Immigrant O visa are typically not required to show proof of onward travel. While some airlines may ask for it, especially during check-in, it is generally advisable to argue your case that it's not needed with a valid visa. Having flexibility in travel plans, like a bus ticket ready, can also ease concerns, though it often turns out to be unnecessary.