A quantum failsafe service (QFS) is disclosed herein. In one example, a first quantum computing device executes a QFS that receives a system stress indicator from a system monitor that tracks a status of the first quantum computing device and/or a status of qubits maintained by the first quantum computing device. The QFS determines, based on the system stress indicator, that a quantum service backup is to be performed for a quantum service running on the first quantum computing device, and obtains a profile snapshot representing a current state of the quantum service. The QFS service then performs superdense encoding of the profile snapshot using a first set of qubits entangled with a second set of qubits of a second quantum computing device, and the first set of qubits are sent to the second quantum computing device (e.g., for storage in a classical data repository, according to some examples).