Techniques are described for generating and presenting a digital document for a transfer. A check service may generate the digital document based on provided check data. The digital document may be stored on a user device and presented to a recipient, for example through the display of the user device. The digital document may also be provided to the recipient in an email or other type of communication. The check service may generate a digital watermark to include on the digital document. The watermark may be unique to the particular document, and may be algorithmically generated based on data that is associated with the particular document, such as a serial identifier, a transaction identifier, an amount, a user identifier of the sender, etc. The digital watermark may be regenerated when the recipient presents the document for payment, to confirm document validity.