"CHIS" stands for CERN Health Insurance Scheme. It is a mutual system, not a private insurance, to which both the Organization and those insured contribute.

These are the three fundamental principles:

Mutuality

Mutuality is based on solidarity among Members. Indeed, the amount of the contribution to the CHIS is not based on the composition of the family, age or medical condition of the insured persons. It is rather in proportion to income, except in cases of voluntary affiliation.
Thus, everyone contributes according to his/her means and makes use of the cover according to his/her needs.

Freedom

CHIS Members benefit not only from a worldwide valid cover but also from freedom of choice of health care providers (doctors, hospitals, clinics).

Responsibility

The freedom, however, is not without limits. The CHIS is a self-financed system. Accordingly, the level of reimbursement shall not exceed the level of contributions. Should this happen, an increase in the contributions would be necessary.
Therefore, CHIS Members are invited to contribute actively to the Scheme's cost-containment policy. Keeping costs under control is the addition of individual actions which help to maintain the financial balance of the Scheme and thus to contain any possible increase in contributions.