Hello,
Me and my boyfriend are flying to Thailand on March 26. I want to apply for a visa for six months, but for that I need proof of a return flight, but we don't have that yet because we don't know when we will return to the Netherlands. Can I also book a ticket to Malaysia as proof or is that not enough?
TLDR : Answer Summary
To apply for a 6-month multiple-entry tourist visa for Thailand, you need to provide evidence of three flights: an entry ticket to Thailand, an exit ticket from Thailand within 60 days, and a subsequent ticket back to Thailand. Booking a flight to Malaysia can serve as valid proof for the exit requirement, as long as it demonstrates that you are leaving Thailand and intending to return.