27. Are there provisions requiring donations to go through the banking system?

"(4) Anyone who makes an one-time contribution of political funds in excess of 1.2 million won or anyone who pays political funds in excess of any of the following amounts according to this Act shall make such contribution and such payment by means of the check, credit card, the payment of such political funds to the deposit account or by other means that make it ascertain the identity of the donor: Provided, That the annual amount of political funds that are permitted to be contributed in cash shall not exceed 20/100 (10/100 of the limited amount of election expenses in the case of election expenses) of the total annual amount of political funds contributed
Article 2, Political Funds Act, 2023"

Sometimes donations must go through the banking system.