Locked SIM Card? Unlock It with These Tips

Haseeb Awan
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June 14, 2023
Modified On
June 14, 2023


A SIM card, short for Subscriber Identity Module, is a small removable card that is inserted into a mobile device, such as a smartphone, tablet, or cellular-enabled smartwatch, to identify and authenticate the device with a mobile network. Being a crucial component for any mobile device that relies on a cellular network for connectivity, the SIM card contains unique identification data that allows the mobile network to identify the device and the subscriber associated with it.

The SIM card stores important information such as the user's phone number, contacts, and text messages, as well as the authentication key used to connect to the mobile network. The main and most popular usage would be having a valid phone number, being able to make or receive calls on a wireless network. It also stores network-specific data such as the user's account information, network access codes, and network service settings.

The tiny card has a cutout on a particular edge and features gold circuits on one surface that link up with a card reader located inside your mobile device. When you insert a SIM card into a mobile device and turn it on, the device communicates with the mobile network using the information stored on the SIM card. This allows you to make and receive calls, send and receive text messages, and access mobile data services such as email, social media, and the internet. Additionally, the fact that a SIM card can be taken out from one gadget and put into another one makes it effortless for you to switch your device without contacting your carrier, enabling you to upgrade your phone seamlessly.

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Why Is Your SIM Card Locked?

There are several reasons why your SIM card may become locked, including entering the wrong PIN code multiple times or attempting to use the SIM card in a device that is locked to another carrier. In some cases, your mobile carrier may also lock your SIM card if you have not used your account in a long time or if there are suspicious activities on your account.

Sometimes, someone may want to lock their SIM card with a PIN code as a security measure to prevent unauthorized access to their device and personal information. This helps to ensure that if their device is lost or stolen, the person who finds or steals it cannot use their SIM card or access their sensitive information.

Read: How to Set Up SIM Card Lock on Android and iPhone?

Why Should You Unlock The SIM Card?

However, this type of locking can also have several drawbacks since it prevents the user from switching to another carrier's service or using the device with different SIM cards. Users will also not be able to make or receive calls, send, receive text messages, and use mobile data services on your device. Unlocking a SIM card will solve all the above problems along with allowing the SIM card to work with other carriers and networks.

How to Unlock Your SIM?

Then what steps should you take to get your SIM unlocked? 

SIM cards are designed with built-in security measures to prevent unauthorized use of the phone number associated with them. The SIM PIN protects your SIM card from unauthorized use, and you will have to enter the SIM PIN to unlock the SIM card. If you enter an incorrect SIM PIN two to three times, your SIM PIN entering page will get locked, and will require you to type in the PUK code.

 If your SIM card is locked, the first thing you will see when you unlock your phone screen will be “enter a SIM PIN”. If you want to get your SIM card unlocked, this is how to unlock a SIM card on both on the android and on the iphone:

1.  Enter the default SIM PIN, which is generally 0000 or 1234.

The default SIM PIN is generally 0000 or 1234. If this is not available, move to step 2.

2.   If the default PIN is not available, enter the wrong PIN code 2-3 times to enter the PUK code page.

If your phone says that the PIN is wrong, or you have set your own PIN code, but have forgotten, getting a PUK code is much easier. There are 2(iPhone) or 3 (android) attempts available for PIN code, and you will move on to the next page, which is entering the PUK code.

3.   Find out PUK code.

There are three ways to know your PUK code. 

  •   Check your SIM card packaging: Your PUK code may be printed on the packaging that your SIM card came in.
  •  Check your carrier's website: Some carriers may provide PUK code information on their website. Log in to your account and look for the PUK code in the support or help section. This process will require your IMEI number, so refer to the following : Open the phone app and enter "*#06#" to display your device's IMEI number
  •  Call customer service: Contact your carrier's customer service hotline and request your PUK code. Be prepared to provide your account information and the SIM card number.

4.   Enter in the PUK code. 

5.   Set a new SIM PIN.

6.   Confirm the new PIN.

If you need to unlock your SIM card, the process will vary depending on your mobile carrier. Here are some links to the customer support pages/ phone numbers for some of the major carriers in the United States:

•   AT&T: https://www.att.com/support/contact-us/

•   Verizon: https://www.verizon.com/support/contact-us/

•   T-Mobile: https://www.t-mobile.com/contact-us

•   Sprint: https://www.sprint.com/en/support/contact-us.html

•   AT&T: 1-800-331-0500

•   Verizon: 1-800-922-0204

•   T-Mobile: 1-877-746-0909

•   Sprint: 1-888-211-4727

They will likely ask you to verify your identity and account information before providing you with the PUK code. It's important to have this information ready before contacting them to expedite the process.

Always remember it's important to enter the code correctly to avoid permanently disabling your SIM card. Once you have entered the PUK code correctly, you should be able to reset your PIN code and start using your device again. Remember to keep your PIN and PUK codes safe and secure to prevent unauthorized access to your device and personal information

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Locked SIM cards can cause serious troubles sometimes; following the steps mentioned above will help you to unlock your SIM fast from any primary carrier.

Haseeb Awan
CEO, Efani Secure Mobile

I founded Efani after being Sim Swapped 4 times. I am an experienced CEO with a demonstrated history of working in the crypto and cybersecurity industry. I provide Secure Mobile Service for influential people to protect them against SIM Swaps, eavesdropping, location tracking, and other mobile security threats. I've been covered in New York Times, The Wall Street Journal, Mashable, Hulu, Nasdaq, Netflix, Techcrunch, Coindesk, etc. Contact me at 855-55-EFANI or haseebawan@efani.com for a confidential assessment to see if we're the right fit!

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