No — only you may use your SIXT account to rent a car. An unauthorized driver has no insurance coverage through SIXT and is personally liable for any damages in full.
What this means for you
Your SIXT rental is tied to your account and your name only.
An unauthorized driver has no insurance coverage through SIXT.
If an unauthorized driver causes damage or an incident, they bear full financial responsibility.
Need someone else to drive?
If another person needs to drive the rental car, they must be listed as an additional driver at the time of booking or at the rental counter. This ensures they're covered under the rental agreement.