Answer
To bring funds into Uruguay, you need documents that confirm their origin. Suitable supporting documents include sales agreements for real estate, movable property, shares, or bonds, as well as the Certificado de origen de los fondos document.
The purpose of such documents is to show not merely that the money exists, but the legitimate trail of how it came to be. The bank needs to understand where the capital originated, who was involved in the transaction, and why this particular amount is being credited to the account or used in the transaction.
The larger the amount, the more carefully the documentation should be prepared: a contract, proof of payment, statements, and a clear description of the funds' path. Fragmented paperwork is less effective than a consistent history from the origin of the funds to the current transfer.