Do I need to have a round-trip ticket?
Regardless of your nationality or visa status, foreign nationals entering the Philippines must have a round-trip ticket. Upon arrival at the airport, you must present proof of a return ticket (a ticket departing the Philippines for a third country after your arrival date) to immigration. Failure to do so may result in denied entry, and you will need to arrange an immediate return flight.
Note: Only those with permanent resident visas, student visas, or expatriate visas are allowed to enter the Philippines with a one-way ticket.