do I need to provide an organogram when opening an account

An organogram is not listed anywhere as a mandatory document

Mostly yes, in practice the bank does provide it anyway — but not because a law requires it. When opening a business account, the bank conducts customer due diligence: it wants to know who manages the enterprise, who owns it and who the UBOs are (ultimate beneficial owners, the natural persons behind the enterprise). An organogram is the most convenient diagram for this, but not a legally required document. What is established, however, are the details from the Trade Register: managers, shareholder structure for certain legal forms, establishments. Those details cover a large part of what the bank wants to see with an organogram.

If you don't have a separate organogram, you can often get by with an extract from the Trade Register plus a brief textual explanation of the structure — especially for a simple private limited company without intermediate holdings. For a group with multiple entities, foreign establishments or a holding structure, the bank often wants to see a diagram anyway, because the extract then does not make it clear at a glance who owns what. This aligns with questions that frequently recur in this type of onboarding process, such as in which countries the enterprise has establishments and under which registration number the company is registered — both are building blocks for precisely the image that an organogram summarizes in one diagram.

Where the underlying data comes from

The basis is the Trade Register Act 2007: it regulates which data of an enterprise are recorded, including managers and, for certain legal forms, the shareholder structure. An organogram itself is not mentioned in that act — it is a tool that banks use within their own customer due diligence, not a legally prescribed attachment. For the question of whether you must provide an organogram, what is therefore mainly relevant is what the bank asks for in its own onboarding process, not an external standard.