How to Manage Default SIM Card Settings on Xiaomi Dual-SIM Phones

Most Xiaomi phones support dual SIM, making them ideal for separating personal and work numbers or using a local SIM while travelling. HyperOS includes powerful dual SIM management tools.

Setting Up Default SIM

1. Insert both SIM cards (SIM 1 and SIM 2 slots, or SIM + eSIM on supported models).
2. Go to Settings → SIM cards & mobile networks.
3. Tap Default SIM settings:
- Calls: Choose SIM 1, SIM 2, or ""Ask every time""
- SMS: Choose preferred SIM
- Mobile data: Choose which SIM provides internet

Tip: Set mobile data to your cheaper/data plan SIM and calls to your main number SIM.

Switching SIM During a Call

To use a different SIM mid-call is not possible — you must end and redial. However, you can change the calling SIM before dialling:
1. Open Phone app → Dial a number.
2. Before tapping Call, select which SIM to use from the SIM toggle button that appears above the keypad.

Intelligent SIM Switching (HyperOS)

Xiaomi's Smart SIM Switch automatically selects the SIM with better signal:
1. Go to Settings → SIM cards → Smart SIM switching.
2. Enable Intelligent calling SIM — the system picks the stronger signal SIM for outgoing calls.

Customising SIM Names and Colours

1. Go to Settings → SIM cards & mobile networks.
2. Tap SIM 1 or SIM 2.
3. Tap the name field to rename (e.g., ""Work"" / ""Personal"").
4. Choose a colour indicator — appears in the status bar and call screen.

Data Roaming per SIM

• Enable or disable roaming independently for each SIM.
• Go to SIM card settings → Data roaming for each SIM.
• Useful for international travel: enable roaming on one SIM only.

Dual SIM and eSIM

Xiaomi 14T, 15 series and newer models support eSIM + physical SIM combinations:
- eSIM acts as SIM 2 in all dual SIM menus.
- Switch eSIM profiles at Settings → SIM cards → eSIM.