German tax authorities may request bank statements

German tax authorities are permitted to request bank statements from taxpayers, including retirees, to verify tax-relevant facts under Section 90 of the Tax Code (Abgabenordnung). While authorities have the right to request documentation to clarify tax matters, they must adhere to the principle of proportionality and cannot conduct unrestricted investigations into private lives without a specific cause.

Retirees with additional income sources, such as rental income, capital gains, or self-employment, may face higher scrutiny. In these cases, the tax office may request bank statements to ensure that all reported income is complete and that claimed expenses are legitimate.