Pillar 3b
In one sentence
Free savings: no ceiling, no lock-in, but no federal tax deduction.
What it changes for you
It complements pillar 3a rather than competing with it: you use it once the 3a ceiling is reached, or when the money must stay available. A few cantons allow a limited deduction on 3b life-insurance premiums, but it is modest and often already used up by health premiums. The simple rule: fill 3a first, then consider 3b.