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Multi-IMSI eSIM: A comprehensive BICS guide

by BICS | October 1, 2025

Multi-IMSI eSIM: A comprehensive BICS guide
clock 11 mins read

The promise of IoT lies in seamless connectivity, but the reality is far more complex once devices start crossing borders. 

IoT solutions often fail to deliver uninterrupted service from logistics trackers to connected medical devices due to coverage gaps, roaming restrictions, and unpredictable costs. 

Traditional roaming SIMs or single-carrier agreements may work within a limited region, but they quickly run into reliability, cost, and scalability issues when devices move globally.

This is why enterprises are turning to smarter solutions such as the multi-IMSI eSIM. 

As a result, many businesses now see multi-IMSI IoT connectivity as the backbone of their global deployments.

When you combine access to multiple carrier networks and roaming agreements within a single card, multi-IMSI SIMs eliminate single-point dependency while unlocking different cost options. This flexibility not only improves resilience but also enables enterprises to optimize connectivity expenses across regions.

In this article, we explore what a multi-IMSI eSIM is, how it works, its benefits, use cases, and how BICS’s IoT solution, eSIM hub, can help enterprises. 

 

What is multi-IMSI and eSIM?

A multi-IMSI SIM card is a powerful leap over traditional SIMs, where it embeds two or more pre-loaded IMSI profiles (International Mobile Subscriber Identities) directly into a single physical SIM. 

Instead of being tied to one network operator, it can intelligently switch between different carrier identities, enabling devices to connect using the most suitable local network as they move across regions. 

To understand why this matters, remember that each IMSI comprises key identifiers:

  • MCC (Mobile Country Code) for the country,
  • MNC (Mobile Network Code) for the operator,
  • MSIN (Mobile Subscriber Identification Number) for the subscriber itself.

When you set up multi-IMSI, it allows the SIM to behave like multiple localized identities, delivering seamless connectivity across borders. 

By intelligently switching to the best available local network, it not only reduces roaming charges but also provides enterprises with more competitive cost structures through multiple roaming agreements. 

Beyond cost savings, multi-IMSI supports next-generation network technologies, including NB-IoT, LTE-M, and 5G, ensuring that IoT devices gain reliable coverage across both traditional mobile networks and low-power wide-area networks. 

This combination of optimized costs and expanded coverage makes multi-IMSI a future-ready solution for the global IoT market.

 

What is eSIM, and how does it work with multi-IMSI? 

An eSIM (embedded SIM) is a programmable SIM built directly into a device, allowing profiles to be downloaded and managed remotely without the need to physically swap cards. 

While eSIM provides flexibility, combining it with multi-IMSI creates an even stronger model, known as a multi-IMSI eSIM. 

In this approach, a single eSIM can store multiple IMSIs, enabling instant local switching while still supporting remote profile provisioning. 

Enterprises get the best of both worlds, which is the resilience and cost optimization of multi-IMSI together with the adaptability and scalability of eSIM.

 

What multi-IMSI is not? 

  • Not multi-SIM phones: Dual SIM slots allow a device to use two physical SIM cards, but they don’t provide automatic network switching.
  • Not eSIM profile downloads: eSIMs require new profiles to be downloaded and managed over the air, which can be slower and more complex than instant multi-IMSI switching.

 

How does multi-IMSI work?

A multi-IMSI SIM is designed to manage connectivity intelligently without relying on repeated over-the-air profile downloads. 

Instead of carrying just one operator identity, the SIM comes with a unique multi-IMSI profile that embeds multiple carrier IMSIs. This allows the device to authenticate with the most suitable local network as soon as it powers on.

Each SIM is manufactured with two essential components:

  • Bootstrap IMSI to guarantee first-time connectivity when the device is activated.
  • Fallback IMSI to ensure service continuity if the active IMSI fails.

The SIM leverages a multi-IMSI applet that manages the logic for selecting and switching IMSIs without requiring manual intervention.

Here’s how the process works:

  1. When a device first registers, the SIM automatically contacts a central SIM server, which identifies the best IMSI for the country or region.
  2. The selected operational IMSI is pushed to the SIM over the air, giving the device access to local network resources.
  3. The SIM continues to check in with the server, which can push new IMSIs if better options become available.
  4. If the operational IMSI encounters an issue, the SIM immediately switches to the Fallback IMSI, maintaining uninterrupted service.

This architecture makes a multi-IMSI SIM card far more seamless than traditional roaming solutions and faster than eSIM models that depend on downloading full profiles OTA. 

Enterprises gain a resilient, scalable way to keep devices online wherever they operate.

 

How can multi-IMSI be combined with eSIM?

Multi-IMSI can also be combined with eSIM technology to enhance flexibility. 

In this model, the eSIM provides the remote provisioning capability, while the embedded multi-IMSI profile ensures instant switching between networks without repeated downloads. 

Together, a multi-IMSI eSIM offers enterprises the speed and resilience of automatic local switching, along with the scalability and lifecycle management benefits of eSIM.

 

Benefits of BICS’ multi-IMSI eSIM solution

 

Delivering seamless global coverage for connected devices

With multi-IMSI SIM, you can connect IoT devices to the strongest available local network in more than 200 countries

This ensures consistent service across regions and supports all major technologies from 2G to 5G, NB-IoT, and LTE-M. 

Businesses gain truly borderless connectivity without dependence on a single operator.

 

Combining multi-IMSI with the BICS eSIM Hub

This is where our multi-IMSI SIM becomes a multi-IMSI eSIM. By pairing it with the BICS eSIM Hub, enterprises gain both instant local switching and remote provisioning. 

A multi-IMSI eSIM is especially valuable for large-scale IoT deployments under GSMA SGP.31/32 standards, for deployments in countries with permanent roaming restrictions, or for industries such as insurance that require global reach with flexible cost and compliance models.

 

Access to global and local profiles for optimized performance

A multi-IMSI eSIM card can hold global bootstrap profiles for first-time activation, global operational profiles for international deployments, and local profiles for in-country optimization. 

Enterprises get the best balance between reach, performance, and cost efficiency.

 

Enhancing reliability through fallback connectivity

IoT applications demand always-on connectivity. With built-in fallback IMSIs, a multi-IMSI eSIM card instantly switches when the active IMSI fails. 

This prevents downtime in critical use cases such as healthcare monitoring, fleet tracking, or industrial automation.

 

Reducing connectivity costs across international operations

Instead of relying on roaming agreements, a multi-IMSI solution uses multiple local IMSIs to minimize charges and avoid unpredictable costs. 

Because each IMSI can represent a different roaming agreement with the same or different networks, enterprises gain flexibility in choosing the most cost-effective option. 

This approach not only reduces expenses across global deployments but also ensures compliance in regions where permanent roaming restrictions are in place, making it a more effective model for long-term IoT growth.

Businesses avoid unpredictable bills and gain a cost model that supports scaling IoT globally while staying profitable.

 

Simplifying operations with one global SIM strategy

Enterprises no longer need to manage multiple SKUs, operator contracts, or manual SIM swaps. 

With multi-IMSI SIMs, businesses can automatically connect to the best network available. 

This simplifies supply chains and reduces management overhead for large-scale deployments.

 

Scaling faster with quicker onboarding and remote provisioning

Multi-IMSI technology enables faster device onboarding compared to downloading new eSIM profiles over the air. When combined with eSIM, it becomes even more powerful. 

A multi-IMSI eSIM not only supports instant local switching but also allows remote lifecycle management at scale. 

This is especially valuable under GSMA SGP.31/32 standards, for global deployments in countries with permanent roaming restrictions, or for industries such as insurance where flexible, compliant, and cost-optimized connectivity is essential.

Businesses benefit from quicker rollouts, easier remote management, and the ability to scale IoT projects without delays.

 

Future-proofing IoT investments against network evolution

With 5G standalone, LPWAN, and new eUICC standards on the horizon, enterprises need solutions that can evolve. 

Multi-IMSI is already compatible with these technologies, ensuring that connectivity investments remain secure and ready for the next generation of IoT.

 

What are the use cases for a multi-IMSI eSIM card? 

 

Use case #1: Enabling uninterrupted fleet tracking in logistics and transport

Cross-border fleets often lose connectivity when trucks or containers move outside a home network. 

Using a multi-IMSI eSIM, transport businesses can now automatically keep vehicles connected to the strongest local carrier. 

Logistics companies gain real-time visibility, reduced downtime, and the ability to optimize routes and delivery schedules without connectivity gaps.

 

Use case #2: Supporting reliable remote monitoring in healthcare

Medical IoT devices such as patient monitors, wearables, or connected diagnostic equipment require constant availability. 

With a multi-IMSI eSIM card, healthcare providers ensure devices connect to the most reliable local network across regions. 

This improves patient safety, supports remote care models, and avoids service interruptions that could compromise treatment.

 

Use case #3: Powering smart city infrastructure with resilient connectivity

Smart city applications such as traffic systems, environmental sensors, and connected utilities depend on continuous, low-latency data flows. 

When you’re using a multi-IMSI eSIM card, it guarantees that devices can switch to the best available carrier when network conditions change. 

The city authorities benefit from a reliable infrastructure that supports long-term digital transformation.

 

Use case #4: Streamlining connectivity for manufacturers and OEMs

Manufacturers building IoT-enabled products for global distribution face challenges with connectivity in different regions. 

Devices can ship globally with one standard configuration by embedding a multi-IMSI solution at the factory stage.

OEMs reduce production complexity, accelerate go-to-market, and deliver products ready to connect anywhere around the world.

 

Use case #5: Ensuring reliable payments in retail and point of sale

Payment terminals and kiosks need always-on connectivity to process transactions. 

Through multi-IMSI eSIM, businesses ensure terminals connect through the strongest available network, even if one carrier experiences downtime. 

Benefits like faster checkouts, fewer failed transactions, and improved customer satisfaction become really profitable for retail brands. 

 

Comparing multi-IMSI with other solutions

 

What are the limitations of traditional roaming SIMs? 

Roaming SIMs allow devices to connect abroad, but they depend on roaming agreements that can be costly and unreliable. 

Network prioritization often favors the home operator, leading to weaker performance internationally. 

For enterprises, this translates into higher costs and unpredictable service quality.

 

What are the challenges of IMSI eSIM profiles managed over the air?

eSIM technology supports multiple profiles, but each new profile must be downloaded and managed remotely. 

This adds latency, increases operational complexity, and requires more signaling overhead. 

While flexible, it can slow down deployments at scale compared to a multi-IMSI eSIM that switches identities instantly.

 

What are the constraints of local SIMs in global deployments?

Local SIMs offer exceptional connectivity in one country, but they lack scalability. 

For a global rollout, you would require sourcing and managing separate SIMs in every market. 

This approach creates operational silos and complicates device lifecycle management.

 

Why is multi-IMSI the balanced solution?

Integrating a multi-IMSI eSIM card gives the combined strengths of global reach and local optimization. 

It switches identities automatically without the overhead of new profile downloads, avoids the high cost of roaming SIMs, and eliminates the complexity of managing multiple local SIMs. 

For enterprises, it delivers a scalable, cost-efficient, and resilient foundation for global IoT connectivity.

The greatest flexibility comes from combining multi-IMSI with eSIM. A multi-IMSI eSIM, powered by the BICS eSIM Hub, delivers both instant local switching and remote profile provisioning. 

This hybrid approach combines the speed of multi-IMSI with the adaptability of eUICC, giving enterprises maximum flexibility to scale IoT globally, even in regions with permanent roaming restrictions or strict compliance needs.

 

Comparing multi-IMSI SIM with traditional SIMs, eSIM, and local SIMs

The following table demonstrates the comparison of multi-IMSI SIM with other solutions, such as traditional, eSIM, and local: 

Solution Strengths Limitations Best Fit
Traditional roaming SIMs Easy initial setup High roaming costs, limited reliability Small-scale, short-term use
Single IMSI eSIM with multiple profiles Flexible, remote provisioning Slow OTA downloads, complex management Enterprise with strong M2M ops
Local SIMs Strong local connectivity Not scalable globally, fragmented operations Domestic-only IoT projects
Multi-IMSI SIM Global + local optimization, seamless switching Requires integration with SIM server logic Scalable global IoT deployments
Multi-IMSI eSIM Instant local switching, remote provisioning, maximum flexibility Needs SIM server and eSIM infrastructure Global deployment with roaming restriction or compliance needs

Unlike a roaming SIM or local SIM, a multi-IMSI eSIM delivers global reach with built-in local optimization.

 

Why choose BICS? 

BICS combines technical innovation with global reach, making it one of the most reliable providers of multi-IMSI eSIM card solutions for large-scale IoT.

  • Unique profile with global and local IMSIs: BICS offers a multi-network eSIM that combines global reach with local optimization in a single profile.
  • Always-on resilience with bootstrap and fallback: A built-in bootstrap IMSI ensures instant activation, while a fallback IMSI guarantees uninterrupted connectivity.
  • Faster switching than OTA eSIM updates: BICS multi-IMSI enables instant network changes, avoiding the delays of single IMSI eSIM profile downloads.
  • Real-time SIM server intelligence: The SIM server continuously selects the best IMSI, ensuring devices always connect to the strongest network.
  • Offering global coverage with enterprise security: Providing connectivity across 200+ countries, reinforced by IPX and SAFE-grade security for compliance and protection.
  • Simplified IoT management: A unified dashboard, layered security, and easy API integration streamline global IoT deployments.

With the BICS eSIM Hub, enterprises get the best of both worlds: the instant switching and cost optimization of multi-IMSI, combined with the flexibility and remote management of eSIM. 

This unique multi-IMSI eSIM capability makes BICS a future-ready partner for global IoT connectivity.

 

Conclusion 

Enterprises cannot afford to let connectivity challenges slow down their IoT ambitions. Multi-IMSI SIM technology ensures that devices connect locally and anywhere in the world, solving the core problems of roaming and reliability.

Leveraging a multi-IMSI eSIM solves the problems of limited coverage, unreliable roaming, and high costs by giving devices the ability to connect locally and securely anywhere in the world. 

Multi-IMSI is the foundation for resilient global IoT with built-in fallback, simplified management, and readiness for future technologies.

BICS takes this one step further by combining multi-IMSI eSIM technology with its eSIM Hub, global reach, enterprise-grade security, and unified IoT management tools. 

The result is a solution that makes global deployments faster, simpler, and more cost-efficient.

To see how BICS can help your business scale IoT without borders, explore our global IoT eSIM Hub.