eSIMs that scale with your IoT

IoT eSIMs for Devices Built to Last

An IoT eSIM is a SIM chip soldered onto a device's circuit board instead of a removable card. Most Millbeck IoT SIMs are available either as a SIM card or as an MFF2 eSIM, so you choose the form that suits your device and keep the same coverage, tariffs and management.

An eSIM suits OEMs building devices in volume, and any device that will be sealed, hard to reach or in service for 10 years or more. Many of our eSIMs also support eUICC, so you can change network profile over the air for the life of the device.

What Is an IoT eSIM?

An IoT eSIM is an embedded SIM, usually in the MFF2 form factor, soldered to the circuit board during manufacture. MFF2 (Machine-to-Machine Form Factor 2) is the standard chip package for embedded SIMs in industrial and IoT devices. See our glossary entry for eSIM (MFF2).

The term eSIM is used in two ways. Strictly, it describes the physical chip. It is also used loosely to mean remote provisioning, which is the job of eUICC. Many IoT eSIMs have both, including many of ours, but not all, so check which a supplier means before you specify.

What Is eUICC and Why Does It Matter?

eUICC (Embedded Universal Integrated Circuit Card) is the GSMA technology that lets a SIM hold several operator profiles and switch between them over the air. An operator profile is the set of credentials that lets a SIM connect to a particular network. See our glossary entry for eUICC.

eUICC matters because a device often outlives the commercial terms it shipped with. If an operator withdraws a network, a country restricts permanent roaming, or you want to change supplier, you can load a new profile remotely instead of sending an engineer to swap the SIM. Many eUICC devices ship with a bootstrap profile, a starter profile used to connect for the first time and download the profile the device will run on.

eSIM or SIM Card: Which Should You Use?

An MFF2 eSIM suits new device designs that will be sealed, shipped to several markets or kept in service for many years. A removable SIM card still suits existing hardware with a SIM slot, short deployments, and sites where swapping a card is quick and cheap.

One SKU for Every Market

An eSIM with eUICC lets an OEM build one version of a product for every market. The same SIM is fitted on the production line, and the right network profile is loaded once the device reaches its country.

This removes per-country SIM variants from the bill of materials, takes SIM handling off the production line, and means a SIM cannot be taken out of a device and used elsewhere. Where a country restricts permanent roaming, such as Brazil and Turkey, we can provide options that keep devices connected in those markets.

SGP.32 and Remote Provisioning

SGP.32 is the GSMA specification for remote SIM provisioning on IoT devices, first published in May 2023. It is built for headless devices (devices with no screen or user) and lets you manage profiles across large numbers of devices from one place.

SGP.32 replaces the earlier M2M approach, SGP.02, where profile changes were controlled from the platform of the operator that supplied the SIM. That made changing supplier slow and dependent on commercial agreements between operators. SGP.32 adds the eIM (eSIM IoT remote Manager), which lets the device owner or their provider manage profiles directly, and borrows the download model used for consumer eSIMs under SGP.22.

SGP.32 is available on some of our eSIMs, not all of them yet, and support across the wider market is still growing. Tell us about your device and we will confirm which of our eSIMs support SGP.32 before you order.

Where Millbeck eSIMs Are Used

Millbeck eSIMs suit devices that are built in volume, sealed, installed in hard places or expected to run for a decade or more. Typical deployments include:

• OEM product lines: connected products built once and shipped to several countries.
• EV Charging: charge points designed for long service lives in outdoor cabinets.
• Smart Buildings: building controls installed in plant rooms and ceilings where nobody wants to swap a SIM.
• Energy and Utilities: metering, substation and network monitoring expected to run for 10 to 15 years.
• Transport: vehicle telematics exposed to constant vibration.
• Industry 4.0: sensors and controllers on factory equipment.

Managing eSIM Estates

Millbeck eSIMs are managed from the same platform as our SIM cards, so a mixed estate of cards and eSIMs sits in one place. You can activate, suspend or retire SIMs, apply group policies, and suspend a SIM automatically when usage passes a threshold you set.

We offer pooled data plans and per GB tariffs, and our API lets you build SIM management into your own systems. Security options such as private APN, fixed IP and IPsec VPN work on eSIMs as they do on SIM cards; see IoT SIM Security.

Frequently Asked Questions

What Is MFF2?

MFF2 (Machine-to-Machine Form Factor 2) is the standard package for an embedded SIM chip in IoT devices. An MFF2 chip is soldered directly to the circuit board, so it cannot be removed and copes better with vibration, temperature changes and moisture than a SIM card in a slot. Most Millbeck IoT SIMs are available as MFF2 eSIMs as well as SIM cards.

Can an eSIM Be Updated After Deployment?

An eSIM with eUICC can receive a new operator profile over the air at any point in the device's life, with no site visit. That lets you change network if an operator withdraws a service, a country's rules change, or you move supplier. An eSIM without eUICC is fixed to one operator profile, so check eUICC support before you specify.

When Should I Use a SIM Card Instead of an eSIM?

A removable SIM card is the better choice for existing hardware with a SIM slot, short deployments, and sites where an engineer can swap a card quickly. An eSIM needs designing into the circuit board, so it suits new products rather than retrofits. Millbeck supplies both, managed from the same platform.

What Is a Bootstrap Profile?

A bootstrap profile is a starter operator profile loaded onto an eUICC SIM at manufacture. It lets a new device connect to a mobile network for the first time, then download and switch to the operational profile it will run on. A bootstrap profile means an OEM can ship one product everywhere and set the network once the device is installed.

Can I Change eSIM Provider Later?

Changing eSIM provider is simpler with SGP.32 than with the older SGP.02 standard. Under SGP.02, profile changes run through the original operator's platform, so a switch depends on agreements between operators. SGP.32 lets the device owner manage profiles directly. SGP.32 is available on some Millbeck eSIMs, and we will confirm support for your device before you order.

Can I Get an eSIM for UK or International Deployments?

Millbeck offers most of its IoT SIMs as MFF2 eSIMs, so an eSIM gets the same coverage as the SIM you choose. Our UK roaming SIMs give unsteered access to EE, O2, Vodafone and Three. Our global roaming SIMs give unsteered access to more than 600 networks in over 180 countries.