Carrier Profile (eSIM)
Carrier Profile (eSIM) is the software bundle that a carrier downloads to a device's eUICC chip to establish a cellular subscription; The profile is created and signed by the carrier on their SM-DP+ server, encrypted with keys specific to the target eUICC chip, and delivered over a secure TLS channel during the activation process; Managing a library of carrier profiles across trips is a practical skill for frequent travelers
Carrier Profile (eSIM) is the software bundle that a carrier downloads to a device’s eUICC chip to establish a cellular subscription. It contains the IMSI, authentication keys (Ki), network access point configurations, and policy settings that allow the device to register on the carrier’s network. Multiple profiles can be stored on the same eSIM chip, but typically only one (or two on DSDS devices) is enabled at any given time.
How it works
The profile is created and signed by the carrier on their SM-DP+ server, encrypted with keys specific to the target eUICC chip, and delivered over a secure TLS channel during the activation process. Once installed, the eUICC’s operating system manages profile lifecycle operations: enable, disable, delete, and export. The profile’s authentication key (Ki) never leaves the eUICC in plaintext, which provides a security property similar to a hardware security module. Disabling a profile does not delete it; the profile remains on the chip and can be re-enabled instantly.
Key facts
- Profile capacity: Most consumer eUICC chips support 5 to 20 stored profiles; deleting unused profiles frees space
- Profile transfer: iOS 16+ and compatible Android devices support eSIM transfer between handsets for some carriers, moving the profile rather than re-downloading it
- Deletion is permanent: Deleting an eSIM profile from a device typically cannot be undone; the carrier must re-provision a new profile
For builders
Managing a library of carrier profiles across trips is a practical skill for frequent travelers. Keeping profiles for frequently visited regions installed but disabled allows instant network activation on arrival without any QR scanning or download steps. The main constraint is chip storage capacity: most devices support enough profiles for 5 to 10 destinations, so periodic cleanup of profiles from locations not revisited keeps headroom available.
Sources
- GSMA. eSIM specifications (SGP.21, SGP.22) for consumer Remote SIM Provisioning. gsma.com
- GSMA. The State of the eSIM Market whitepaper. gsma.com
- ITU. Recommendation E.118: International telecommunication charge card / ICCID structure. itu.int
- 3GPP. Mobile network specifications portal. 3gpp.org
- FCC. Consumer guides on wireless devices and unlocking. fcc.gov
