A system includes a secondary computing device not owned by a user, a hardware processor, a memory and instructions that cause the processor to generate a transient wallet identifier (ID) for a transient mobile wallet, the transient mobile wallet being of limited duration, and provide a configuration user interface the user, presenting configuration information for the transient mobile wallet. The processor also identifies a usage specification for the transient mobile wallet defining allowed uses for the transient mobile wallet. The processor also activates the transient mobile wallet on the secondary computing device, receives a payment transaction approval request, compares the payment transaction data to the usage specification, determines that the payment transaction data is non-conforming, and transmits a rejection message for the first payment transaction.