Methods and systems that prevent completion of postdated financial transactions until the specified future date is provided. A portion of the information necessary to complete a financial transaction is encrypted utilizing an identity-based encryption (IBE) scheme. The encryption key used to encrypt the information is associated with the date on which the transaction is authorized to be completed. The encrypted information is provided to the payee. The issuing bank provides a daily decryption key that allows decryption of information encrypted using the key associated with the corresponding date. Thus, only when the maturity date of the transaction has arrived will the payee or depositing bank be able to obtain the decryption key that will decrypt the encrypted information necessary to complete the transaction. Since the encrypted information can not be decrypted until the date associated with the encryption key, the financial transaction can not be completed until such date.