@thims If you are on a B permit, you get taxed at source. Unlike swiss citizens and those on a C permit. So you won't have to fill in a steuererklärung (filing taxes) for the first 5 years.
Because of this, if you live in kanton Zürich, you will be taxed an average tax rate from the whole canton. Not actually the one from your city. So if your town has higher taxes than the base rate of the canton (steuerfuss 100), you will actually pay more when filing taxes. Because then the effective rate of your town will be applied. Which might eat up all or most of your savings from paying into pillar 3a.
So for example if you live in the city of Zurich itself, it doesnt make financial sense to pay into 3a, instead of just investing it on your own.
I guess if your town has a lower than 100 tax rate, it would be double worth it to pay into 3a. Because you would get the savings from 3a and also the additional savings from switching to the average to your towns real rax rate.
So make sure to check what the tax rate (Steuerfuss) in your particular town is before paying into 3a. Because you might potentially generate a higher tax bill and also a bunch of additional work for yourself this way.