How onward travel requirements work around the world
Requirements for proof of onward travel are set by each country's immigration authority and enforced by airlines at check-in. Rules can change with visa policy updates, public health measures, or even individual officer discretion.
Some countries publish clear rules. Others rely on airline practice: even when immigration would let you in, the airline may refuse boarding without an onward ticket because they would be fined if you were refused entry.
The list below covers destinations where travelers commonly report being asked for proof of onward travel. Use it as a guideline, not a guarantee. If you tend to travel without a return ticket, staying prepared is the simplest way to avoid surprises at the gate.