Request tax identification number (IdNr) or church tax deduction feature (KiStAM)
Source: BUS Rheinland-PfalzIn order to withhold church tax on capital gains tax, those obliged to withhold church tax, for example banks, must ask the Federal Central Tax Office (BZSt) whether their customers are liable for church tax.
You will need the tax identification number (IdNr) of the taxpayer to make the inquiry. If you do not have the tax identification number, you can request it at the same time.
You submit your request via the BZSt online portal (BOP).
To be able to submit the request via the BOP, you must first register your company there. The registration process can take up to 3 weeks.