What Is an MFF2 SIM? Embedded (Soldered) SIMs Explained
MFF2 is the tiny soldered SIM chip built into IoT devices, cars and trackers. Learn how it differs from the eSIM on your phone and what it means for travel.
Updated 16 October 2026
In one sentence
An MFF2 SIM is a tiny, rugged SIM chip, about 6 x 5 mm, that is soldered directly onto a device's circuit board so it can never be popped out.
In detail
MFF2 (Machine-to-Machine Form Factor 2) is a SIM package defined for devices that must run for years without anyone touching them, such as vehicle trackers, smart meters, industrial sensors and in-car emergency call systems. Because it is soldered down, it resists vibration, moisture, heat and tampering far better than a plastic card in a slot. Many MFF2 chips are also eUICC, which means the carrier profile inside can be swapped remotely instead of replacing hardware. The standards behind this include the GSMA's M2M specification (SGP.02) and the newer IoT eSIM specification (SGP.32), which is designed for devices with no screen or user interface.
How it works
The chip is manufactured as a small surface-mount package and soldered onto the board during assembly, just like any other component. If it is an eUICC version, the device or its management platform can download a new carrier profile over the air, so the same hardware can switch networks without a technician visiting. IoT devices have no screen for a person to scan or tap, so a management platform handles the profile switch in the background.
Why travellers should care
You will not buy an MFF2 SIM for a trip, but you may already rely on one inside a rental car, GPS tracker, dashcam or mobile Wi-Fi hotspot. For your own phone or tablet, a travel eSIM is the right tool: with Fresim-powered stores the plan arrives by email, you tap Install on iPhone (iOS 17.4+) or Install on Android (Android 10+), and it is set up. The QR code is the easy backup for sharing the eSIM or installing it from another screen.
Related terms
- M2M
- IoT connectivity
- industrial eSIM
- eUICC
- connected devices
Example
A courier company fits 500 delivery vans with GPS trackers that have an MFF2 chip soldered inside. When the vans start crossing borders, the company switches the chips to a regional carrier profile from a dashboard, with no mechanic opening a single tracker. Meanwhile, a driver in one of those vans uses a travel eSIM on their own phone for maps and messaging, installed with one tap.
Key takeaway
MFF2 is the soldered, long-life SIM for machines, while travellers should look for a phone-friendly eSIM they can install in one tap.
Frequently asked questions
What does MFF2 stand for?
MFF2 stands for Machine-to-Machine Form Factor 2. It describes a small surface-mount SIM package, roughly 6 x 5 mm, that is soldered onto a circuit board instead of sitting in a removable tray or slot.
Is an MFF2 SIM the same as an eSIM?
Not exactly. MFF2 describes the physical shape and soldered mounting. eSIM usually refers to the ability to download and switch carrier profiles remotely, known as eUICC. Many MFF2 chips are eUICC, but some are fixed to one carrier.
Can I use an MFF2 SIM in my phone?
No. MFF2 chips are designed to be soldered during manufacturing, so you cannot buy one and add it to a phone. For travel, install a standard eSIM plan instead, using the Install button on iPhone (iOS 17.4+) or Android (Android 10+).
Why do IoT devices use soldered SIMs?
Soldered SIMs handle vibration, moisture, dust and wide temperature ranges better than plastic cards, and they cannot be stolen or knocked loose. That makes them a good fit for meters, trackers, vehicles and outdoor sensors that run for years.
What is the difference between SGP.22 and SGP.32?
SGP.22 is the GSMA specification for consumer eSIMs in phones and tablets, where a person installs profiles. SGP.32 is the newer specification for IoT devices, which are managed remotely because they often have no screen or buttons.
Where you'll use this
More esim glossary
Sources
- GSMA — SGP.32 eSIM IoT Technical Specification
- GSMA — SGP.22 RSP Technical Specification (Consumer eSIM)
- GSMA — SGP.02 Remote Provisioning Architecture for Embedded UICC (M2M)
- ETSI — ETSI TS 102 221 UICC-Terminal Interface Characteristics