To check if your phone is carrier locked, look in the settings for "Carrier Lock" or "Network Provider" status (iPhone: Settings > General > About; Android: Settings > Connections > Mobile Networks/Operators) for "No SIM restrictions" (unlocked) or a carrier name (locked). The most definitive test is inserting a SIM card from a different carrier; if it prompts for an unlock code or says "SIM not supported," it's locked.
Android
On Android, the closed lock icon may appear in the SIM status or mobile network settings. If you're trying to switch carriers or use a travel SIM, this icon is a red flag. You'll need to contact your current carrier to request an unlock.
Test with a different SIM card
You only need to power off the phone and remove the current SIM card. Then, switch it to an active SIM card from a different carrier and turn the phone back on. If you can call or text with the new SIM successfully, you have an unlocked phone.
Yes, your IMEI number will tell if your phone is unlocked. You can put the IMEI number in an IMEI number checker website to check the unlock status of your phone.
How to check if an Android phone is unlocked
Quick Tip: Test Your Samsung Phone with *#0*# Before buying a Samsung phone, use the code *#0*# to check its hardware! This secret menu lets you test the screen, buttons, speakers, sensors, and more. It's a quick way to ensure everything works perfectly and avoid issues later.
For Android devices
You can insert your SIM card into an unlocked phone and it will function seamlessly, allowing you to continue using your existing phone number and cellular service. The first indication that the phone is unlocked is that it detects the SIM card by connecting to the network and finding reception.
Contact your mobile service provider and say you want to unlock your phone. Your service provider will review your account to confirm you meet all requirements to have your phone unlocked for free. You may not be eligible to unlock your phone if you owe money or have not fulfilled the service contract.
Network Lock
You will need to contact the original service provider or retailer to request an unlock code. Some service providers may allow you to unlock the device for a small charge or for free, whereas others may not allow the device to be unlocked at all.
The simplest way to unlock your device is to get in touch with your provider and ask for a Network Unlock Code (NUC). This is typically easy and free to get – if you've finished your pay-monthly contract, networks aren't allowed to charge you unlocking fees at all.
A SIM lock, simlock, network lock, carrier lock or (master) subsidy lock is a technical restriction built into GSM and CDMA mobile phones by mobile phone manufacturers for use by service providers to restrict the use of these phones to specific countries and/or networks.
Use an online IMEI checker
Once you've found your IMEI number, you can see if your iPhone is unlocked by plugging it into an online database. There are many of these sites available (search “online IMEI checker”) but most or all will take you to a paywall to find out the device's SIM lock status or carrier status.
Unlocking your phone means you can use any network's Sim card, giving you the freedom to switch providers, lower costs and allows you to pass your phone on to others. Your network won't charge you to unlock your phone if you're out of contract, though if you're still in contract or on pay-as-you-go, they may.
Insert a different carrier's SIM card and power on your Android phone. Check if the phone accepts the new SIM card: Try making a call with the new SIM card. If the call connects, your Android is carrier-unlocked. If not, the phone is locked to a specific carrier.
Visit our Carrier Unlock Guide to contact your carrier for help on checking your device's status.
Yes it will, do remember a locked phone, will only work on the mobile service provider that the phone is registered to. You will need to request from your mobile service provider to have the device unlock so you can use a different sim card please.
Changing your SIM card will not cause you to lose data that is stored in the cloud or on your device internal storage.
Enable or Disable SIM PIN Lock on Android Smartphones
Typing *#0*# (star-hash-zero-star-hash) into the phone dialer on a Samsung device opens a hidden General Test Mode, a secret diagnostic menu used for checking hardware components like the screen (touch, color), sensors, speakers, cameras, and vibration. It's a valuable tool for users to self-diagnose issues or verify a device's functionality, especially when buying a used phone, as it allows you to test functions like touch responsiveness, RGB colors, and sensor accuracy.
A PUK (Personal Unlocking Key) is an 8-digit code that unlocks your SIM if the PIN has been entered incorrectly three times.
3️⃣ Dial *#2663# to refresh your Wi-Fi and boost internet speed. Click on TSP FW Update for touch screen firmware updates.
The Samsung secret code *#9900# opens the SysDump menu, primarily used to delete temporary junk files (dumpstate/logcat) to free up space and potentially speed up your device, and also offers options like resetting battery statistics for better performance. It's a shortcut to system functions for maintenance, allowing users to clear logs and manage battery data, but should be used with caution as it accesses system-level functions.
Dialing *#7353# on a Samsung phone opens the Quick Test Menu, a hidden diagnostic tool that lets you quickly test various hardware components like the speaker, vibration motor, sensors (accelerometer, light), touchscreen, camera, and display colors, all through simple, one-tap options for basic troubleshooting. It's a handy way to check if parts of your phone are working without needing complex apps, though some codes may vary or not work on newer models.