Let's discover the smart card contained in your GSM mobile phone (and every mobile device).
What is a SIM card?
A SIM card with a microprocessor base is similar to a mini-computer with its operating system, storage, and built-in security features.
The SIM card can add, delete, and manipulate information within its memory on top of sending and receiving data.
A SIM card can be replaced by users and slides easily into a slot within your phone or mobile device.
SIM full form
When configured with modern cryptography, as recommended by NIST, BSI, ANSSI, SIMalliance, etc., SIM cards provide a state-of-the-art security level.
Types of SIM cards
Different form factors (FF) co-exist:
- The credit-card sized SIM is obsolete
- A regular SIM or 2FF measures 15 millimeters by 25 mm
- A smaller version of the SIM called the micro-SIM, or 3FF SIM card (Third Form Factor), is 12mm by 15mm
- The nano-SIM or 4FF is 8.8 mm by 12.3 mm
- The eSIM or embedded SIM is not removable and comes either plugged-in or soldered. Its size 6mm by 5mm, and its thickness is 0,67 mm.
SIM market size in 2021
Overall, according to Eurosmart, 5.4B secure elements (from SIM cards to eSIMs) have been shipped in 2019.
The consolidation of MNOs is impacting an already mature market.
2020 is flat as 5G is not deployed enough to impact the SIM market significantly.
With the pandemic, lower demand for smartphones but increased need for connectivity stabilized the market in 2020. Eurosmart is forecasting a 1% growth for 2021.
According to Telcoprofessionnals, top SIM card manufacturers include Thales, Giesecke & Devrient, Idemia (Morpho and Oberthur Technologies), Bluefish, Datang, DZCARD, to name a few.
What is a SIM card used for?
Designed initially to access mobile phone networks, it authenticates the subscriber and ensures the user is accurately billed for used airtime.
The SIM also stores your phone directories, messages, information on roaming across different networks, and many other value-added voice and data services.
End-users can instantly access news, games, chat, and dating services along with mobile payment applications with an easy-to-use interface.
The handset model does not restrict it. This feature enables operators to reach all of their customers.
SIM technology: key for operators
Operator-centered services such as call completion and automatic handset configuration help reduce their customer billing costs and increase their Average Revenue per User (ARPU).
The SIM is the final link in the chain between networks and end-users, and no customer can connect to the network without their SIM.
Network operators can communicate, download applications, and manage a SIM card remotely using Over-the-Air (OTA) technology.
For example, network operators can update the SIM cards with new applications and services without requiring users to upgrade their handsets or visit a store location.
Where do we fit in?
Thales is a primary SIM card manufacturer and global solution and service provider.
Thales SIM cards provide interoperability and compliance with the latest standards, including new form factors such as the 4FF (Third Form Factor) or the eSIM (embedded SIM).
This feature ensures that our SIM cards can connect to networks across the globe with any mobile phone or portable device (such as PDAs or Tablet computers).
Thales also provides devices, software, and systems to manage everything from a single user's SIM card to an operator's entire distribution of SIM cards.
More resources on SIM cards and related technologies
- What so special about smart cards? A short overview of smart cards in 3 minutes
- GSM and CDMA: what's the difference?
- What are 2G, 3G, 4G, and now 5G? Learn more on 5G speed and technology and 4G LTE
- What is VOLTE for mobile users and the IoT?
- What is an embedded SIM or eSIM? Please see below
- The Mobile economy in 2019 (white paper from GSMA)
- Sim Tool Kit
- Why do we need a new kind of SIM?

Definition & benefits of a 5G SIM for 5G virtualized networks
Trust is increasingly perceived as a pervasive transversal factor to be added to virtualized 5G architecture in order to help to deliver the full 5G promises.
Learn more