What Information is Stored in A SIM Card?
Bryan HolidayShare
A SIM card allows you to connect to cellular networks that send and receive data. It stores the data it receives, such as phone numbers, call logs, country codes, and authentication keys. You may think that's all it can do, but that's not correct.
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Table of Contents
A SIM card can hold more data than phone numbers or call logs. Wondering what data that is? Let's find out.
What Kinds of Data Do SIM Cards Store?
SIM cards contain information about your local network and two authentication passwords: your personal identification number (PIN) and personal unblocking key (PUK). Both these numbers are used for security purposes.
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But that's not all. Here are other data stored by SIM cards:
- Authentication key
- Local area identity
- Mobile country code
- Service provider name
- Service dialing number
- Unblocking code
- Integrates circuit card ID.
Your SIM card or eSIM can also store your IMEI number.
How Much Storage Does a SIM Card Have?
A typical SIM car has storage limits ranging from 8 KB to 256 KB. The space may not seem like a lot, but it can simultaneously hold up to 250 contacts. It saves your contacts when you change your device.
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SIMs can also store text messages. However, these are deleted during a factory reset. Fortunately, most devices these days come with sophisticated cloud platforms that allow you to store more rich data like emails, addresses, and even pictures of your contacts. You can store your messages on the platform too.
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How Does Roaming Work in SIM Cards?
If you go to another country and wish to use your local provider, you'll have to go into roaming mode. That means you can use your local network no matter where you go.
Most SIM card issuers have preferred networks stored in a numerical format on the SIM. When the SIM card moves out of the range of these registered networks in a country abroad, then the SIM card connects to the best network available.
For a slightly different angle on the same thing, see How Often Should a SIM Card Be Replaced: A Comprehensive Guide.

Which Security Codes Are Stored in SIM Cards?
SIM cards hold vulnerable information that hackers can target, such as your email, social media accounts, and banking information. If the hacker cracks the authentication tests, they can access the crucial information stored on your SIM card and transfer it to another SIM.
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However, SIM cards have a security code to prevent security breaches. Users can go to their SIM card settings and change their PIN code to make their phones more secure. Encryption and two-way authentication can also be done to protect data.
Read this, then The Ultimate Europe Travel Guide, and you're set.
SIM Card Formats
SIMs come in different sizes. You can have a standard-sized SIM, a mini SIM, a micro SIM, or a nano SIM. Most devices use a nano-SIM these days. Before choosing a SIM card size, you should always check your device's requirements.
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However, despite the size differences, all SIM cards hold the same information and storage space. A nano SIM doesn't have much more space than a standard or mini-sized SIM card.
Thanks for visiting our blog, are you planing to travel to Europe? Check out our range UK SIM card before you take off.
Before you take off make sure to check with local government of the travel status.
Written by
Bryan Holiday

