Is Your Phone Locked or Unlocked? What to Know Before Buying a SIM or eSIM

Planning to buy a SIM card or eSIM for your phone? Before you do, it’s important to check whether your phone is locked or unlocked. This can make a big difference — especially if you’re switching carriers, travelling internationally, or buying from a third-party seller.
🔓 What Is an Unlocked Phone?
An unlocked phone is not tied to any specific mobile network. You can use it with any carrier that supports the device, simply by inserting a SIM card or activating an eSIM.
Benefits of an unlocked phone:
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You can switch providers freely
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Ideal for international travel
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Works with most prepaid, travel, and data-only SIMs and eSIMs
🔒 What Is a Locked Phone?
A locked phone is restricted to work only with the carrier it was originally sold by. These are common when:
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The phone is on a payment plan or contract
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It was purchased directly from a mobile provider
Things to note:
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A locked phone will usually reject SIM cards or eSIMs from other providers
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Some carriers require you to pay off the device or wait a certain time before unlocking
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Unlocking a phone is often free once eligible, but some carriers may charge a fee
✅ How to Check if Your Phone Is Locked
For iPhone:
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Open
Settings > General > About
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Scroll down to Carrier Lock
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If it says "No SIM restrictions", the phone is unlocked
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If it shows a network name or mentions a restriction, it is locked
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Note: Older iOS versions may not display this. In that case, try inserting another SIM card as described below.
For Android:
Exact steps can vary slightly by brand, but here are the most common methods:
Option 1: Insert a SIM Card from a Different Carrier
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If your phone connects to the network, it’s unlocked
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If you see a message like "SIM not supported" or "Enter unlock code", the phone is locked
Option 2: Check Mobile Network Settings
Go to:
Settings > Connections > Mobile Networks > Network Operators
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If you can see and choose other carriers, the phone is likely unlocked
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If options are restricted, it may be locked
🔍 Optional: Check with IMEI
You can check the lock status or device history using your IMEI number:
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Dial
*#06#
or find it inSettings > About Phone
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Visit a website like imei.info or use your carrier’s official IMEI tool
This may tell you:
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If the device is locked
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If it has been reported lost or stolen (blacklisted)
📲 Before You Buy a SIM or eSIM
Here are the key things to check before purchasing:
✅ Is your phone unlocked?
Make sure it will accept SIMs or eSIMs from other carriers.
✅ Is your phone compatible with the provider’s network?
Not all phones support every network type or frequency band — especially with eSIMs or international carriers.
✅ Does your phone support eSIM (if that’s what you're buying)?
You can usually find this in your phone’s specs, or by checking the settings.