Tourist and Business visas are not required for citizens of the United States for a stay of up to 30 days. However, your passport must have at least one blank visa page and be valid for six months. If your passport is expiring you can view the requirements here.
Fast Passports & Visas always recommend checking with your airline as requirements may change without notice.
Citizens of most countries are required to have a valid visa to enter the Philippines. The Filipino Consulate General determines the duration of visa upon receiving an application.

Business: The Filipino business visa is designed to allow business travelers to come to the Philippines in order to pursue business activities, such as attending meetings and conferences.  However, it excludes holders from seeking employment in the Philippines.
Tourist:  The tourist visa (also known as the ‘visitor visa’ or ‘visit visa’) allows the holder entry to the Philippines, but strictly forbids travelers from engaging in any work while in the Philippines.  Filipino tourist visa holders can also not extend their stay beyond the visa limits.