Most tourists aren't aware but when departing from the Philippines you have to pay an airport fee, which is roughly around $13 (~550 Philippine Pesos), though the airport fee is different depending on which international airport you use in the Philippines.
Well, nothing new about this. Airport fees are very common in most airports. It's just that in European airports and back here in the US the airport fee is added to your plan ticket automatically. In the Philippines, you must pay that at the airport before departure and you have no choice.
Travel Tax The Terminal fees vary from airport to airport and season to season but 750php is the most you will pay. By the way, there's also a Travel Tax that is charged but this only applies to Filipinos leaving the country to go abroad..just thought to mention this.
Just to clarify that this domestic airport fee for all the terminals of NAIA is already added to the plane ticket so you will not need to pay unless you bought your ticket before August 2012. It's only the international flights terminal fee of Php550 that has not been yet incorporated to plane ticket that you still have to pay it at the airport before proceeding to the immigration counters.