One-way or round-trip?
Very common in Mexico. 'Sencillo' means 'simple/single' and 'redondo' means 'round,' making it a direct conceptual translation.
A slightly more complete or formal way to ask. 'Solo ida' means 'only going.'
Use this phrase to state that you want a one-way ticket.
Use this phrase to state that you want a round-trip ticket.
At the ticket office: 'Hello, a ticket to Bogotá, please.' 'Of course, one-way or round-trip?'
I want a round-trip ticket to Lima. I leave on Monday and return on Sunday.
Buying a one-way ticket is cheaper if you don't know when you want to come back.
For the train, do you prefer one-way or round-trip?
The phrase '¿Sencillo o redondo?' is extremely common, sometimes even more so than '¿ida o ida y vuelta?'.
'Ida y vuelta' is standard. The word for ticket is 'billete' instead of the more common Latin American 'boleto' or 'pasaje'.
'Ida y regreso' is frequently used, substituting 'regreso' (return) for 'vuelta'. However, 'ida y vuelta' is also perfectly understood.
'Ida y vuelta' is the standard phrase. The word for a ticket is almost always 'pasaje'.
Quiero un boleto de un camino. — This is a literal translation of 'one way' but 'camino' means 'road' or 'path.' For tickets, the correct term is 'ida' (going) or 'sencillo' (single).
Necesito un viaje circular. — While 'circular' means round, this phrase sounds like you want to travel in a literal circle. The correct idiomatic expressions are 'ida y vuelta' (going and return) or 'viaje redondo' (round trip).
Usar 'un redondo' solo. — Saying 'Quiero un redondo' is incorrect. You must say 'un boleto redondo' or 'un viaje redondo.' The same applies to 'sencillo' ('un boleto sencillo').