Here are some resources I found useful for the topic of FIRE in Germany:
Der Privatier
Frugalisten
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These links specifically for this topic:
der-privatier
frugalisten
When you are in the withdrawal phase i.e. you no longer work and are living off your investments, only your capital gains count as income. e.g. You could withdrawal 40.000 € from your investment account on Jan 1 to pay for the year's expenses, however that entire 40.000 € is unlikely to all be capital gains; a portion will include your own investment capital, which you don't pay taxes on.
So let's say from that 40.000 €, 10.000 € is your original invested capital and 30.000 € is capital gains. Your income for that year will be 30.000 €, and that is what you pay tax on.
According to the
calculator posted by PandaMunich, your monthly health insurance contribution will be 480 €. However your health insurance contributions can be deducted from your taxes as
vorsorgeaufwendungen:
After the deduction, your taxable income for this year is now 24.240 €.
Capital gains tax in Germany is 26.375%. You would have a tax bill of:
24.240 € * 26.375% =
6393 €.
However you can ask the Finanzamt to perform a
Günstigerprüfung, which allows you to pay basic income tax instead of capital gains tax. Unless you have very high income, this usually results in a lower tax rate.
According to the
basic tax income table, your income tax for the year will be:
24.240 € * 12% =
2854 €.
So in the following year, you probably want to withdraw an extra 3.000 € to cover the tax owed in the previous year.
When selling your shares, the oldest shares are always sold first. This is called First In, First Out or FiFo. Because these shares have been invested for longer, they will have a higher capital gain, resulting in more taxes to pay when you sell them. However there is a trick you can use to have more control over which shares are sold:
Steuerhack 3: Das LiFo-Prinzip
So it's possible to reduce your income even further, therefore paying less health insurance contribution and less income tax.
I hope nothing I wrote here is incorrect or misleading.