When traveling abroad, it's smart to understand the local etiquette. Some countries eschew tipping, but in the Philippines, it's usually expected. Many companies, including restaurants and hotels will include a service charge, but you shouldn't consider this to be the only tip. It's still appropriate to leave an additional amount for those who offered great service, especially since the "little guy" may not actually see any of the money that comes from the service charge.
To Whom and How Much
Tips should go to the same types of workers you'd tip in America: wait staff, bartenders, doormen, taxi drivers and massage therapists. Beyond that, you could also give a tip to anyone who went especially out of the way to help you, such as a hotel concierge or a tour guide. According to TripAdvisor.com, an appropriate tip is usually around 10 percent of the bill. Leave more for exceptional service, and leave less, or none at all, if the service was poor.