SIM lock or Subscriber Identity Module lock is a function that lets the carrier of your SIM card lock it from its end. You will not be able to do any SIM-supported activity. So, what does SIM locked mean on iPhone?
Haven’t you ever come across unlocked cell phones on online shopping sites? So what does an unlocked phone mean? iPhone’s SIM lock was initially exclusive to AT&T in the US. But now brands like Verizon, T-Mobile, etc, also block SIM cards. It is basically to restrict the user from using other SIM cards. When the restriction is lifted, it is called an unlocked phone or an unlocked iPhone.
So, what does SIM locked mean on iPhone? Well, it means either of three things; A- You have forgotten the SIM PIN; B- You are trying to use a SIM that your current carrier doesn’t allow. And C- You are in a country where your carrier doesn’t provide service.
What Does SIM Locked Mean on iPhone?

SIM lock is a software restriction. It is implemented by service providers to restrict users from using SIM cards from other service providers. This generally comes with connections that come with bundled packages by Verizon, T-Mobile, AT&T, etc.
In bundled packages, companies offer cell phones and connections at a significantly lower price. This is the reason they put software restrictions like SIM lock. The phone might only work with the bundled SIM card and no other SIM card. You have to get your iPhone SIM unlocked in order to use other SIM cards.
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Why Are Some iPhones SIM Locked?

As mentioned above, Apple introduced SIM lock in collaboration with AT&T. It was implemented to compel users to use the same SIM until the contract with the service provider ended.
Later, Apple and carrier companies started collaborating to sell bundled packages that included some data plans and iPhones at low prices.
When the price is low, and the data plan is free, the companies have to be profiting from elsewhere. So, they implement SIM lock to make you stay on the same service for a particular period of time.
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How to Unlock a SIM Card on an iPhone?

Now that you know what SIM locked means on iPhone, why don’t you move on to learning how to unlock a SIM card on an iPhone? I will talk about two methods here. Remember that these are the only ways. Any website or video says something else; bunk it!
Method 1: Using SIM PIN
1. Go to Settings on your iPhone.
2. Select Phone.
3. Scroll down to find SIM PIN and tap on it.
4. Toggle off the SIM PIN switch. This is a signal to your phone that you want to unlock the SIM card.
If the SIM PIN button is already turned off and your SIM is still locked, you will have to call your service provider.
5. Enter your SIM PIN.
Once again, if you don’t know your SIM PIN, contact your service provider.
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Method 2: Getting an Unlock Code From Your Carrier
This is how to unlock a SIM card on an iPhone that is locked by the carrier. If you are not being able to use any SIM card on your iPhone except the one that you are using now, follow these steps:
1. Call your carrier’s Customer Support. You can try dialing *611 or 611, as these are the default customer support numbers on most phones.
- AT&T Customer Service – 1 (800) 331-0500
- T-Mobile Customer Service – 1 (800) 922-0204
- Sprint Customer Service – 1 (888) 211-4727
- Verizon Customer Service – 1 (877)-746-0909
Keep your carrier account PIN within reach. You will need that to verify your identity.
2. You will reach an automated assistant. Communicate and convey your problem. To get a real human to talk to, try saying something like, “I want to remove on SIM card.” This should get you connected to a customer service representative.
3. Ask the customer service representative for a PIN unlock code. Explain to them that you are only trying to unlock your SIM card, not the iPhone itself.
If you have put in the wrong PIN too many times, your unlock code will be a PUK code.
4. Note down your PIN unlock code. You will unlock your SIM with this 4-digit PIN.
Head to Apple Support Community for more Q&A.
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Wrapping Up
When you come across “SIM unlocked iPhones,” the question that must have struck you is, “what does SIM locked mean on iPhone?” Well, now you know the answer. You also know how to unlock a SIM card on an iPhone. Just remember not to guess your PIN. If you forgot it, call your carrier’s customer support. And as always, I’ll see you next time. Until then, Ciao!