Absolutely. Modern smartphones featuring Dual SIM Dual Standby (DSDS) technology allow you to simultaneously operate both your primary physical SIM card and your CoreESIM. This configuration is highly advantageous, as it enables you to keep your existing number active for calls and SMS (especially for receiving critical two-factor authentication codes) while dedicating your CoreESIM for high-speed local data in your travel destination. You can easily manage preferred lines for data, calls, and messages within your device's cellular settings.
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Can I retain my primary physical SIM card while using CoreESIM?
Updated April 22, 2026
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