Multi-IMSI or eUICC? How to Pick the Best Fit for Your IoT Deployment

Quick summary: multi-IMSI vs eUICC

Multi-IMSI and eUICC are two technologies used to provide flexible and scalable cellular connectivity in IoT devices. Multi-IMSI enables SIMs to switch between multiple subscriber identities, while eUICC allows remote provisioning of SIM profiles. Both offer advantages in global deployments, but differ in complexity, control, and cost. Understanding their differences is essential for IoT solution designers, network engineers, and product managers.

What Is Multi-IMSI?

Multi-IMSI (International Mobile Subscriber Identity) is a SIM technology that allows a single SIM card to store and use multiple IMSIs. Each IMSI corresponds to a different mobile network operator (MNO), allowing the SIM to switch networks dynamically without physical replacement.

How multi-IMSI works in IoT

• The SIM comes preloaded with several IMSIs.

• The device selects an IMSI based on signal strength, availability, policy, or geography.

• Switching can occur over-the-air (OTA) without backend provisioning platforms.

• Typically managed by the SIM provider through custom firmware or OTA platforms. 

What Is eUICC?

eUICC (Embedded Universal Integrated Circuit Card) is a standardized SIM technology defined by GSMA. It enables the remote provisioning, deletion, and management of SIM profiles over-the-air. eUICC supports multiple profiles but only one can be active at a time.

How eUICC works in IoT

• A device contains an eUICC-compliant SIM or embedded SIM (eSIM).

• Remote SIM Provisioning (RSP) platforms download, install, or switch SIM profiles as needed.

• Allows seamless change of network providers without swapping the SIM.

• Compliant with GSMA standards for interoperability and security.

Benefits & challenges of multi-IMSI in IoT

Benefits

• Fast network switching: Near-instant IMSI switching without relying on external infrastructure.

• Lower complexity: No need for GSMA-compliant platforms or agreements.

• Network redundancy: Improved uptime in areas with poor coverage.

• Cost-effective for small/medium deployments.

Challenges

• Vendor lock-in: IMSIs must be preloaded and managed by the SIM provider.

• Limited scalability: Harder to scale globally without carrier agreements.

• Non-standardized: Less industry alignment compared to eUICC.

Benefits & challenges of eUICC in IoT

Benefits

• Carrier flexibility: Profiles from multiple MNOs can be provisioned OTA.

• Global scalability: Ideal for devices manufactured once and shipped globally.

• Remote lifecycle management: Profiles can be added, removed, or changed anytime.

• Standards-based: GSMA compliance ensures interoperability and security.

Challenges

• Higher complexity: Requires integration with Remote SIM Provisioning (RSP) platforms.

• Increased costs: Development, certification, and MNO integration can be expensive.

• Slower profile switching: Typically takes longer than Multi-IMSI swaps.

Multi-IMSI vs eUICC: Feature comparison

Which should you use?

• Use multi-IMSI if you need fast switching, cost-effective regional coverage, and lower deployment complexity.

• Use eUICC for global IoT products requiring full carrier flexibility, compliance with GSMA standards, and future-proofing via remote management.

Both multi-IMSI and eUICC offer viable solutions for connecting IoT devices across borders and networks but serve different needs. Multi-IMSI excels in speed and simplicity, while eUICC delivers flexibility and long-term scalability. The right choice depends on your deployment model, geographic scope, and need for remote control.

Ready to choose the right SIM strategy for your IoT deployment?

Explore how Pelion can help you optimize connectivity with the right mix of flexibility, control, and scalability.