Can eSIM have the same number?

Can Your Phone Number Live on Both a Physical SIM and an eSIM Simultaneously?

The short answer is no. While eSIMs offer a convenient alternative to traditional physical SIM cards, they operate independently. This means a single phone number cannot be active on both a physical SIM and an eSIM within the same device at the same time.

This independent operation is key to how mobile networks manage your connection. Each SIM card, whether physical or electronic, is assigned a unique International Mobile Subscriber Identity (IMSI) number, which is fundamentally tied to your phone number. Think of the IMSI as the digital key that unlocks your network access. Having two identical IMSIs active simultaneously would cause significant network conflicts and prevent your carrier from reliably routing calls and data.

So, what happens if you want to switch from a physical SIM to an eSIM, or vice-versa? Your mobile carrier facilitates this transition by porting your number. This process effectively transfers your phone number from one SIM’s IMSI to the other. During the porting process, your number is briefly deactivated on the old SIM and then activated on the new one. This ensures seamless service continuity, minimizing any disruption to your calls, texts, and data access.

The advantage of this system is straightforward: it prevents ambiguity and ensures reliable network performance. Imagine the chaos if your carrier received two signals from identical IMSIs, both claiming the same phone number. The network would be unable to accurately determine which SIM to route your calls and data to, resulting in dropped calls, failed messages, and general connectivity issues.

Therefore, while you can certainly migrate your number between a physical SIM and an eSIM, the magic isn’t in having both active simultaneously. The separate and independent nature of each SIM ensures a stable and reliable connection for your mobile services. The porting process, offered by your mobile provider, provides the seamless transition needed to switch between the two SIM types without losing your precious phone number.