In France, you must have public or private health insurance that covers part of your healthcare expenses. Your status (student, employee, etc.), determines which Social Security programme you must register for.
Which Social Security programme must you register for?
If you have a work contract, doctoral fellowship or other contract, you are automatically registered for general Social Security. Your employer pays your contributions for you.
If you do not have a work contract and you are under 28 years of age, you must register for Student Social Security at the same time as you enrol at the university. It costs approximately 250 euros per year.
If you do not have a work contract and you are over 28, you must take private health insurance, at your expense.
Take out complementary health insurance to be reimbursed more.
On average, Social Security reimburses 70% of medical expenses. For better coverage, you can take out complementary health insurance, called a "mutuelle": it will entitle you to be reimbursed to up to 100% of your medical expenses.
For more information on healthcare in France, check the page Healthcare, Social Security and Complementary Health Insurance.