Is PhilHealth coverage mandatory for all Filipinos?

Yes. Put another way, PhilHealth membership is compulsory.

SEC. 6. Coverage. - All citizens of the Philippines shall be covered by the National Health Insurance Program. In accordance with the principles of universality and compulsory coverage enunciated in Section 2 (b) and 2 (1) hereof, implementation of the Program shall, furthermore, be gradual and phased in over a period of not more than fifteen (15) years: Provided, That the Program shall not be made compulsory in certain provinces and cities until the Corporation shall be able to ensure that members in such localities shall have reasonable access to adequate and acceptable health care services. (underlining supplied)

Reference: Art. III, Sec. 6, R.A. 7875 

SECTION 4. Objective – It is the main objective of the NHIP to provide all Filipinos with the mechanism to gain financial access to quality health care services within the first 15 years of its implementation. Coverage of the employed members in the government and private sectors, individually-paying, retirees, and indigent families shall be ensured. (underlining supplied)

Reference: Title III, Rule 1, Sec. 4, IRR of R.A. 7875

Please note though, that membership and eligibility to avail of benefits are two different things. You may be a member, but if you are not paying your PhilHealth contributions with the required frequency, you are not eligible to avail of your PhilHealth benefits.

This applies to everyone who is employed, regardless if it is with the government or the private sector, or Overseas Filipino Workers (OFWs).

Individually Paying Members (IPMs) may or may not choose to register or pay premiums under the IPM program. If they choose not to, they are not eligible for PhilHealth benefits. It is strongly recommended that those qualified as IPMs register and pay their contributions.

Lifetime members need not pay as they are already retired and have already made at least 120 monthly contributions.

The contributions for those belonging to sponsored program are paid for by government or private entities.

For further information on who can enroll or register as a PhilHealth member, read this post.