a bank kérdéseket tesz fel egy nagyobb befizetésről a számlámon, hogyan válaszoljak

Origin and purpose of the transaction, not the bank itself

The bank does not ask this out of curiosity, but because the Law on the prevention of money laundering and financing of terrorism (Wwft) requires it to conduct customer due diligence as soon as a transaction deviates from the normal pattern. Usually it wants to know two things: where the money comes from and why it is now entering in this amount. That is a different question than with an insurer or in a sustainability list — why a bank asks something different than an insurer when it is about the same subject is precisely this difference in purpose.

As an answer, usually a short, factual description suffices: which agreement or invoice underlies the payment, who the counterparty is, and a copy of the underlying document — invoice, contract, or sales agreement. If you do not have this at hand, answer that you will investigate it instead of filling in something you cannot substantiate; a guess that later turns out to be wrong is more annoying than a day's delay. Origin of assets is by the way a broader question than just this one transaction — if the bank asks for that separately, it is about a vállalkozás vagyonának eredete, not about this specific payment.

Basis: the customer due diligence from the Wwft

These questions arise from the customer due diligence that the Wwft imposes on banks: they must assess unusual transactions and report them if necessary, and for that they must be able to understand the background of the money. That is separate from the trade register — the Trade Register Act 2007 establishes who represents the enterprise, but says nothing about the origin of individual payments. If the question comes together with a request to confirm the UBOs, then that is about another part of the customer due diligence; see for that kik a vállalkozás végső haszonélvezői.