Hi there,
Self-employed individuals are legally entitled to make much larger contributions to 3a retirement savings solutions than employed individuals. In 2017, for example, self-employed individuals can contribute up to CHF 33,840 to 3a retirement savings. Employees can only contribute CHF 6768.
When you become employed and join a 2a occupational pension fund, you may be entitled to make voluntary 2a contributions to close any gaps in your pension. Gaps are made up of the difference between the (lower) amount you contributed to your 2a pension fund in the past and the amount you are currently required to contribute based on your current salary.
If you contributed more to the third pillar (3a) during your self-employment than the maximum 3a contribution allowed for employed individuals, the difference between the 3a contribution limit for employees and the higher contributions you made when you were self-employed must be deducted from possible gaps in your 2a pension fund.
Example: You are self-employed for 3 years during which time you contributed CHF 50,000 more to your 3a savings than you would have been entitled to contribute as an employee. When you become employed again, you have a CHF 60,000 "gap" in your 2a occupational pension fund which could normally be filled with voluntary 2a contributions. However, the CHF 50,000 which you contributed to your 3a savings above the employee limit must be deducted from that "gap". So you will only be eligible to make CHF 10,000 in voluntary contributions to your 2a pension fund.
Because your new 2a occupational pension fund has to determine your "gap" and your eligibility for voluntary contributions, they need to know how much you contributed to your 3a retirement savings while you were self-employed. You will need to provide your pension fund with this information if asked.
Best regards from Moneyguru
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3a retirement savings account comparison