Generally speaking, methods and media for authorizing a guest to use an electronic financial transaction card, such as a credit card or debit card, are disclosed. Embodiments may include receiving information about a desired guest transaction (which may be limited in size, timeframe, nature, etc.) from a customer associated with an EFT card, generating a guest PIN number and artifact information for the guest transaction, and transmitting them to the customer. Embodiments may also include receiving from a financial terminal a PIN number and an indication of a supplied artifact associated with a proposed transaction utilizing the EFT card. Embodiments may include determining whether the proposed transaction should be authorized based on the received PIN number and the supplied artifact and, in response to determining that the proposed transaction should be authorized, transmitting approval of the proposed transaction to the financial terminal.