No,if you are from a EU continental country using Visa On Arrival.
what kind of nonsense is this. This forum has gone really downhill. All EU citizens need an onward ticket when they are getting the visa-exempt stamp on arrival and the Thais are within their rights to deny you entry into the country if you don't have one. However this will almost certainly not happen as you won't get to Bangkok in the first place, as the airline you are flying with will very likely not let you get on the plane at all. In fact they should have made it clear to you when you booked the one-way ticket that you are not allowed into Thailand using a visa-exempt stamp without an onward ticket out of Thailand.
