Should I book a return ticket for my 3-month trip to Thailand?

When planning a trip to Thailand for 3 months, it's advisable to have an onward or return ticket, especially if you're traveling without a visa. Most airlines require proof of an onward flight during check-in, and failure to present one may lead to being denied boarding. Some travelers suggest booking a one-way ticket shortly before departure for a low cost, or opting for an open return ticket that can be changed later. Always verify your airline's specific policies to avoid complications.