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What Can Someone Do If They Put My SIM Card In Their Phone?

What Can Someone Do If They Put My SIM Card In Their Phone?

Mobile phones store our credentials and private information. A stolen or lost sim card can be an even bigger issue than we can imagine. A hacker or thief can access your private information and use it for a number of misdeeds. 

If someone puts your SIM card in their phone, provided the SIM is network compatible and unprotected, they may be able to impersonate you, send and receive calls and messages as you, use your data plan, access your social accounts, sell your information, and possibly gain access to your bank account. 

In this article, we explain what someone can do if they get their hands on your sim card and what protective measures you should take to stop them. 

See also: How Do I Change My Number On My Android Phone?

Can someone else use your SIM card on their phone?

Whether or not someone can use your sim card in their phone depends on three factors:

  • Carrier lock: many phones come locked to a specific carrier SIM card. It means that the device can only be used with that particular carrier SIM. This restriction may be built into both GSM and CDMA phones.

    In most cases, the lock can be removed by entering a numeric passcode provided by the carrier. The unlocking process takes some time, and if you’ve reported the stolen phone, then the thief will not be able to request a passcode or unlock your mobile. 
  • Active and compatible SIM card: an active sim card is ready for use and has a valid plan with a carrier. Your sim card must be both network compatible (2G, 3G, and 4G) and size compatible (standard, micro, and nano) to be used in another device. You can check the network and size compatibility of any smartphone on GSMArena
  • Pin code: if your SIM card has a pin code, then no one else can access it on their phone. However, most sim cards have a default pin code of 0000. It’s the most predictable pin and must be changed when you activate the sim’s pin code. 

What can you do with someone’s SIM card?

A sim card can be used in several illegal and immoral activities. Here are a few things that a hacker or scammer can do with your sim card:

  • Impersonate you: hackers are always after your personal information. They can use that information to clone identities, online shopping, steal money, and build credit card debts. 
  • Send and receive calls and text messages: anyone with your sim card and contacts can send and receive illegal or unethical messages to someone else. They can also receive phone calls and call others on your behalf (without your knowledge).
  • Use your paid service: spammers can use your sim’s services such as messages, calls, and data that will be charged on your account. 
  • Create a Social Media Account: with your sim card, anyone can activate WhatsApp or create social media accounts without your knowledge.
  • Access certain personal information: even if the sim card is inactive, they can still access your contacts and other data such as text messages stored on your sim card.

Can someone hack into your bank account with your SIM card?

Can someone hack into your bank account with your SIM card?

SIM card scam is one of the hottest trends among scammer hackers. Not only do they obtain your personal information via your sim card, but also gain access to your bank account. Here’s how it works:

Access your bank account using your SIM

It all starts with getting your basic information like name, email, and phone number. That info is used to gain access to more personal information like social media accounts.

The second step is phishing, where they send spam emails and messages with spammy links. Once they have enough information, they contact your cell phone carrier and pretend to be you. They report your SIM card stolen and get a new one in your name.

With the sim card, the possibilities are limitless. They have direct access to all two-factor authentication codes. That means they can access social media and email.

From there, they can obtain any information including your bank account number, credit card number, shopping accounts, and potentially your parent’s or spouse’s information too. 

Identity theft using your SIM

As if stealing your information and money wasn’t enough, your information may be given to scammers and hackers who can use it to clone identities and use it to do any misdeed like stealing money, etc.

What information can someone get from my SIM card?

In a modern smartphone such as iPhone or Android phone, most information is usually not stored on the sim card. On an iPhone, contacts, and text messages are stored on iCloud, and in Android, they’re on Google Drive unless you explicitly choose otherwise.

Pictures, videos, and other media are stored in the phone memory or SD card. Therefore, with a smartphone, your information is mostly safe. 

If you own an old phone, however, the data is likely stored in the SIM card and hence may be easily compromised. That said, if your SIM card has a pin code in place, no one will be able to use the SIM or access data on it.

If someone puts my SIM card into their phone, will they see my text messages?

In modern smartphones, messages are stored on the phone and not on the SIM card. Therefore, if someone puts your sim card into their phone, they won’t be able to see the messages you received on the old phone.

However, they can see all the messages that they receive after putting your SIM card on their phone. 

The above only applies to text messages on your SIM card, not other services like WhatsApp and Telegram. These applications use your mobile number for authentication. So If your SIM card is compromised, the accounts are also compromised along with all messages and data on the platform.

Can I temporarily place my SIM card in someone else’s active phone?

You can place your SIM card in someone else’s active phone if it’s not a carrier phone (locked to a specific carrier). Also, the person’s device must be network and size compatible with your SIM card for you to be able to insert it.

An unlocked phone is not tied to a specific network and can work with SIM cards from any network. Most modern devices are compatible with GSM (2G), HSPA+ (3G), or LTE (4G). These devices will work with any carrier.

The phone’s SIM slot size (standard, micro, and nano), however, must be compatible with your SIM card.

Can I give my SIM card to someone else?

Lending someone your SIM card, either temporarily or permanently, can be risky. SIM cloning happens physically by placing the sim card on a card reader attached to a computer with duplication software. 

Once your SIM card is cloned, someone can read and access anything that you can read and access through your SIM card. That’s even more dangerous than SIM card swapping, as in some cases, you may not even be aware of cloning.

A SIM card is like your social security number or email address for your mobile phone. You don’t just hand over your social security or email to someone else no matter who they are. Likewise, it’s unadvisable to lend your SIM card to someone else no matter how trustworthy they are. 

Should I keep my old SIM card?

If your SIM card has been successfully deactivated, there’s no point in keeping the card itself. The gold chip on the sim card cannot be recycled.

It’s safest to destroy a sim card instead of just throwing it away. Even deactivated, it can store some information like contacts or old messages. Take a pair of scissors to break the SIM card into small pieces before throwing it away. 

On the other hand, if the SIM card is not deactivated, keep it safe when you’re not using it.

What to do if my SIM card was stolen?

A stolen SIM card is a pretty dangerous situation and you must take action immediately. Here’s what to do if your SIM was stolen:

  • Report to the carrier: most snatching and theft cases happen at night, so it may not be possible to immediately visit the franchise to deactivate and get a new SIM card. Therefore the first step should be to report the stolen sim card to the carrier. Once you’ve registered the complaint, the carrier will take appropriate action and block it temporarily.
  • Get an old SIM card deactivated by ordering a new one: when you order a new SIM, your old one is automatically deactivated. Therefore, ordering a new sim card is a good option when your sim card is stolen.

Can I track my SIM card that was stolen?

In case of theft, law enforcement agencies use IMEI numbers to trace mobile phones instead of mobile numbers. That’s because the thief can simply take out your sim and throw it away. However, there are a few ways to track your sim card that was stolen:

  • Call your mobile number from another phone. That way, the carrier can trace the last known location of your cell phone. 
  • Find your mobile’s IMEI number on its original box. It’s given by the GSM network and is unique to every mobile device. IMEI number is used by your network provider to locate lost phones and prevent thieves from connecting to a network.
  • Request assistance from your network provider. They detect the change of the original sim card and use the IMEI number to trace the new sim card. 
  • Contact law enforcement and report your stolen cell phone. They can block your mobile device and the thief will not be able to use it for calls or messages.