The Xiaomi 15 supports Dual SIM Dual Standby (DSDS), allowing you to have two SIM cards active on standby but only one can be used for calls or data at a time.
For your reference, here are the advantages of DSDS on the Xiaomi 15:
1. Both SIM cards can be active on standby, meaning you can receive calls or messages on either number, but you can only use one SIM for voice or data at a time;
2. With this feature, you don’t need to carry two phones for work and personal numbers;
3. This feature is especially useful if you want to manage both personal and work numbers on a single device while maintaining network flexibility.