Assalamu alaykum, Sheikh. I’m a self-employed freelancer in Germany and must pay taxes. Is it allowed to open a separate Bank Account so my business/tax matters stay separate from my private account? Otherwise it would get mixed up and I’d get very confused. JazakAllahu khayran.

Yes, there is nothing wrong in itself with keeping a separate account so that your business and tax matters do not get mixed with your private money. What the ruling turns on is the bank and the account, so if an Islamic bank is available then deal with it, and if there is none then to the extent of the need and without taking interest, unless there are other valid options to take care of the problem.