Introduction
In this article, you will learn what an eSIM is, how it works, and how it compares to traditional physical SIM cards.
An eSIM (embedded SIM) is a digital SIM card that allows you to activate a cellular plan without using a physical SIM card. Instead of inserting a removable card into your device, an eSIM is a programmable chip built directly into your phone or tablet.
An eSIM functions exactly like a traditional SIM card - it connects your device to a mobile network and enables cellular connectivity. Most new smartphones and tablets support eSIM technology today, though some older devices may not have this capability.
How eSIMs work
Installation is simple and requires only an internet connection and a unique digital code, typically provided as a QR code. Once your eSIM is activated and provisioned by Saily, you can access it without an internet connection. The initial setup requires internet to download the eSIM profile, but after that, the eSIM functions normally for cellular connectivity.
eSIMs provide the same signal strength as physical SIM cards, and they do not drain your phone battery any differently. If you experience network issues, they're typically caused by coverage limitations, not the type of SIM card you're using.
eSIM vs. Physical SIM
Both eSIMs and physical SIM cards serve the same purpose in the context of mobile connectivity: connecting your device to a mobile network. The main differences are:
- Physical Form: A physical SIM is a removable plastic card; an eSIM is a digital chip built into your device.
- Installation: Physical SIMs require opening your device's SIM tray; eSIMs install digitally through a QR code or app.
- Portability: An eSIM must be deleted from one device before installing on another, while physical SIMs can be easily moved between devices.
- Dual SIM Support: eSIMs free up the physical SIM tray slot, allowing some devices to support two eSIMs, two physical SIMs, or one of each.
- Convenience: eSIMs can be activated instantly before you travel, while physical SIM cards require visiting a store or waiting for delivery.
Using multiple phone numbers
You can have two phone numbers on one phone if your device supports dual SIM technology. This allows you to hold two eSIMs, two physical SIMs, or one of each. This is useful for separating work and personal numbers, or for using local SIM cards while traveling without removing your home carrier's SIM.
However, each SIM card, whether physical or digital, supports one unique phone number. You cannot have the same phone number on both a physical SIM and an eSIM simultaneously.
If you want to convert your existing phone number from a physical SIM to an eSIM, you'll need to contact your network provider. They will move your number to the eSIM and disable the physical SIM card.
Managing your eSIM
There's nothing unsafe about removing an eSIM from your device. If your data package expires, you have no more use for it, or you need to free up an eSIM slot for a new plan, you can safely remove it at any time. If your data plan is not depleted or expired, you can reinstall your eSIM on the same device or a different compatible device through your eSIM provider's app.
eSIMs can be tracked just like physical SIM cards - your location can be identified through your carrier's network, regardless of which type of SIM you're using.
Additional tips
- Learn how to install the Saily eSIM on your iOS or Android.
- Check if Saily covers your desired travel destination.
- Read our guide on what Saily is.
