An excellent primer on PhilHealth

The Philippine Health Insurance Corporation or Philhealth is a government owned and controlled corporation (GOCC) founded on February 5, 1995. Its main goal is to ensure the health of every Filipino through social health insurance regardless of social status: poor, rich, young, old, sick, healthy, working or jobless. To achieve this, all premiums paid by members are pooled nationally and in effect, there is a cross-subsidization across districts.

Source: Essential Things About PhilHealth Contribution, Requirements and Benefits