In Switzerland, the term Old Age and Survivors Insurance (OASI) refers to a government-regulated pension scheme run by regional social security offices.
The scheme guarantees a basic old-age pension to its members when they reach legal retirement age. It also guarantees a basic pension to surviving dependents in the event of death.
Membership in this scheme is obligatory for all adult individuals residing in Switzerland, regardless of whether residents are employed, self-employed or unemployed.
When OASI members are employed, contributions to the scheme are shared evenly between the employee and the employer. Unemployed, self-employed individuals and individuals who are employed by foreign companies must cover the full contribution themselves.
In addition to old age pensions, the scheme also pays out survivors pensions to the dependents of insured individuals in the event of their death. This life insurance is meant to provide basic financial protection for the dependents of adult residents of Switzerland.
The pensions paid out by both the old-age and the survivors insurance are based on the amount paid in premiums up until the point at which the benefit is claimed. Individuals (and dependents of deceased individuals) who have only contributed to the scheme for a relatively short amount of time, or who have only contributed the minimum required contribution will receive a pension which reflects the premiums paid.
Swiss citizens and citizens of European Union (EU) and European Free Trade Association (EFTA) countries who have resided in Switzerland and paid OASI contributions for 5 consecutive years or more have the option of voluntarily participating in the scheme after leaving Switzerland and relocating to a country which is not a member of the EU or EFTA.
You can find more information about the OASI under the pillar 1a definition.