Complementary insurances aren’t mandatory; they cover a wider range of services, such as private or semiprivate rooms during hospital stays.

Advantages:

• Complementary insurances widen the range of refundable services.
• They help cover the expenses of alternative medicine
• They provide an upgrade in the room service in hospitals (private or
  semiprivaterooms for instance)

Subtleties:

• Bear in mind that insurers aren’t forced to accept you for a complementary
  insurance.
• Insurance premiums vary depending on age, gender and health
• You can contract your basic insurance and complementary insurance with
  two different insurers.
• You can cancel complementary insurances; contractual delays and
  cancellation notices depend on the insurer. You can consult the CGA,
  or your insurance policy.

Advice:

Take the time to examine the services offered by your complementary insurances and compare them with what your basic insurances offers.