What's the big deal about eSIM? Only everything.

By: Jim Beaugez on Feb 1, 2022 1:13:15 PM


Get ready to ditch your phone's SIM card. The days of needing that tiny chip to use your mobile device are coming to an end. The SIM card is going digital, and emerging eSIM technology will be a game-changer for you and for wireless carriers. So, what the heck is eSIM exactly?

To get to eSIM, you first need to know what a SIM card does. That’s easy enough—a SIM is the small plastic card that fits into the side of your mobile phone or device and connects it to a cellular network. SIM is an acronym for Subscriber Identity Module, and it contains basic information about the user and the network it connects to. Whenever you change or upgrade devices, the SIM card follows you to the new device.

eSIM performs the same functions as a traditional SIM, but the card is embedded in the device’s circuitry instead of inserted in an external card slot on the device. This reduces the device’s size, and that could result in smaller devices with more space for storage and other goodies.

The importance of eSIM is what it allows you to do. Want to combine your personal and work numbers on a single device? Not a problem. eSIM enables you to have multiple phone lines on the same device. What’s more, it will enable a completely digital experience so you can activate your devices in seconds while avoiding an often-complicated onboarding process.

“With eSIM, consumers can finish onboarding very quickly in a fully digital environment,” says Marla P. Rogers, Ph.D., DMTS, who is a subscriber management architect at C Spire. “This increases security, because with the eSIM embedded in the device no one can take your device, remove the SIM card and use it in another device.”

We’ve been involved in the development of eSIM to ensure our network would be in sync with and support eSIM for smart phones, tablets and other devices. Now we’re using it as the foundation for the future of the C Spire network.

And you don’t have to wait to see eSIM in action. Some devices already use eSIM—like the smart watch on your wrist—and the consumer internet of things (IoT) will rapidly expand thanks to eSIM, further digitizing our lives. We hope you’re excited. We are.

C Spire is a privately-held telecommunications and technology company driven to deliver the best experiences in wireless, fiber internet, and business IT solutions such as internet, VoIP, cloud and managed services. Read more news releases and announcements at For more information, visit or find us on Facebook, Twitter or Instagram.