If you use an eSIM and another SIM together, many phones let you choose which line is used by default for calls.
This is useful for travelers who want to use a home number for calls while keeping a travel eSIM for data.
Quick answer: Open SIM or Cellular settings and select your preferred line as the default for voice calls.
Important: Call line controls depend on phone model, software version, carrier settings, and our General Conditions.
Why Choose a Default Call Line?
- Keep using your normal number
- Use a travel line if preferred
- Avoid choosing a SIM every call
- Separate business and personal lines
- Simplify dual SIM travel setup
Tip: Many travelers use the eSIM for data and their main SIM for calls.
How to Choose Default Call Line on iPhone
- Open Settings
- Tap Cellular or Mobile Data
- Tap Default Voice Line
- Select your preferred SIM or eSIM
Helpful guides:
How to Choose Default Call Line on Android
- Open Settings
- Go to SIM Manager, Connections, or Network Settings
- Tap Calls or default SIM preferences
- Select the preferred line
Menu wording varies by brand.
Helpful guide: Dual SIM Setup Guide
Can I Choose Per Contact?
Some phones can remember the last used line or allow line choice each time you call.
This depends on the device.
What If I Want eSIM for Data Only?
This is a very common travel setup:
- Main SIM = calls & SMS
- Travel eSIM = mobile data
How to Check If eSIM Is Using Data
What If Calls Use the Wrong SIM?
Check these settings:
- Default voice line
- Recent call line memory
- Dual SIM preferences
- Line disabled accidentally
Will This Affect Mobile Data?
Usually no. Call line and mobile data line are often separate settings.
Best Travel Setup Example
- Main SIM for calls
- Main SIM for SMS codes
- Travel eSIM for mobile data
- Roaming disabled on main SIM data if desired
Why This Matters for Travelers
Without proper settings, users may place calls from the wrong number or face unexpected charges.
A clear default line makes travel easier.
Need travel data now? Browse NoveSIM travel eSIM plans.
Premium Traveler Tip
Before departure, make one test call to confirm the correct line is selected.
Final Thoughts
Many dual SIM phones let you choose a default line for calls separately from mobile data.
This is one of the best ways to optimize travel eSIM use.
FAQ
Can I choose which SIM is used for calls?
Yes, many phones allow a default voice line setting.
Can I use eSIM for data and main SIM for calls?
Yes, this is a common travel setup.
Will changing call line affect data?
Usually no, they are separate settings.
Can Android phones do this too?
Many Android dual SIM phones support similar options.
Why are calls using the wrong SIM?
Check your default voice line settings.
