The IMEI (International Mobile Equipment Identity) is a unique 15-digit code assigned to every cellular device. This includes smartphones, cellular tablets, and smartwatches.
US carriers like AT&T, Verizon, and T-Mobile use the IMEI to identify hardware, authorize network access, and monitor a device's security status. Without this system, cellular networks simply couldn't tell the difference between a legally purchased smartphone and a stolen one. You can use the active verification form provided on this page to query global databases and check your device's history.
If your phone supports dual-SIM technology (a physical SIM and an eSIM), it will have two identifiers: IMEI1 and IMEI2. Both numbers point to the same physical device, but they represent different network connection pathways. Verifying both codes ensures that neither slot is blocked by carriers.
Why You Need to Check the IMEI Before Buying
Checking the IMEI before buying a used phone is crucial. It reveals if the device is reported stolen, blacklisted, or tied to an unpaid carrier account.
If someone stops paying their carrier installment plan, or if a phone is reported lost, the carrier places a network block on that specific IMEI. Sometimes, sellers try to offload these blocked phones on peer-to-peer marketplaces before the bans fully update across the network.
Expert Tip: Always match the IMEI displayed on the screen (by dialing *#06#) with the one printed on the physical box or SIM tray. This ensures the motherboard hasn't been swapped into a stolen housing.
Many comprehensive IMEI checking tools can also flag activation locks tied to cloud accounts (such as Apple's iCloud or Google's Factory Reset Protection). While the global IMEI database focuses on network blocking, third-party services use your IMEI to identify the hardware and cross-reference it with the manufacturer's cloud servers. Let's say a previous owner performs a factory reset without properly signing out. In that case, the phone will still request their original credentials upon startup. Running your code through a checker that includes an activation lock report helps you avoid buying a device you can't even activate.
How to Find the IMEI on Any Smartphone
Retrieving your IMEI is standardized across all Android and iOS platforms. You can find it using the dialer, inspecting the physical device, or navigating the system settings. It's usually best to rely on multiple methods. This is especially true if the phone has screen damage or you suspect software tampering.
1. By Dialing *#06#
Open your phone app and dial *#06# on the keypad. The IMEI will instantly pop up on your screen.
This method relies on an MMI (Man-Machine Interface) code to query the device's firmware directly. Unlike network-based codes, this command is processed locally by the phone itself. Because it pulls data straight from the hardware and works even without a SIM card or active cellular connection, it is the fastest and most reliable way to extract the true IMEI.
2. On the Physical Device and Box
If the device won't turn on, physical engravings are your best bet. You can typically find the IMEI in these locations:
- On the SIM card tray: Common on many Apple iPhone models. Eject the tray to read the microscopic numbers on the outer edge.
- On the back glass or chassis: Often laser-etched or printed on a specialized sticker on Samsung and other Android devices.
- Under the removable battery: Typical for older smartphone models.
- On the original retail box: Look for a robust sticker containing the model number, serial number, and network identity codes near the barcode.
3. In Device Settings
This software-level check provides the precise device identity data currently running on the motherboard.
- iOS: Go to Settings > General > About. Scroll down to find the physical and electronic SIM network identification section.
- Android: Go to Settings > About Phone (or About Device) > Status.
Note: Many modern systems allow you to long-press the number to copy it directly to your clipboard.
What Information Does the IMEI Number Reveal?
Running the IMEI through a verification database confirms the exact model name. It also checks the financial status with major US carriers to see if the device is fully paid off or still financed under an equipment installment plan.
Most importantly, it checks the global blacklist status, which dictates whether the phone can legally broadcast a cellular signal.
A standard 15-digit equipment identifier is composed of three distinct structural segments. The first eight digits constitute the Type Allocation Code (TAC), which serves to identify the specific manufacturer brand and the exact device model version. This is followed by a six-digit Serial Number (positions 9 through 14) that uniquely identifies the individual hardware unit within that particular production line. Finally, the 15th position is reserved for a Check Digit, which utilizes a mathematical algorithm to validate the structural integrity of the entire code string.
IMEI Versus Serial Number
The IMEI is a universal standard regulated by an external global telecommunications body. Cellular carriers use it to manage network access and security.
The serial number, on the other hand, is a proprietary, variable-length alphanumeric string. The manufacturer creates it to track factory production, warranty claims, and retail inventory. Carriers do not use serial numbers to block phones.
How the Global Blacklist System Works
When a phone is reported stolen or lost, the carrier adds its IMEI to a central Equipment Identity Register managed by the GSMA.
Before this shared database existed, a stolen AT&T phone could easily be activated on T-Mobile. Now, when a carrier flags an IMEI locally, it pushes the update to the global registry. Within hours to several days (depending on the country), participating carriers download the list, blocking the device from the global cellular network.
A blacklisted phone loses all baseband privileges, though it can still connect to Wi-Fi networks. The mathematical integrity of the IMEI is verified using the Luhn algorithm. This checksum formula easily detects manual typing errors.
What to Do If You Discover a Blacklisted IMEI
If an IMEI check returns a blacklisted status while you are with a private seller, abandon the transaction immediately.
If you already bought the device online, leverage buyer protection policies on platforms like PayPal, eBay, or Swappa. Take a screenshot of the failed verification report and submit a formal claim stating the item cannot be activated.
Ignore third-party services offering to "unblacklist" or clean the device for a fee. These are unauthorized, temporary software manipulations. Only the original account holder can legally request the removal of a carrier block by paying the outstanding balance or verifying they recovered their lost property.
