What Is IMEI Number? | Complete Beginner’s Guide 2026

Many buyers lose money every year by purchasing stolen or blacklisted phones from online marketplaces. One common scenario: a device works initially, then suddenly loses network access because the IMEI was previously reported stolen. Understanding IMEI numbers helps prevent such situations.

In 2026, every phone – whether it's a budget Android or a flagship foldable – has a unique identity: the IMEI number. Think of it as your phone's hardware identifier, similar to a serial number but standardized globally. It is designed to remain permanently assigned to the device.

Here's the reality: most people have no idea what that 15-digit number on their phone box actually means. They see it when they dial *#06#, shrug, and move on. But understanding IMEI can help you avoid buying stolen goods, assist in reporting a lost phone, and understand how device identity works in modern networks.

This guide provides researched information about IMEI standards, practical tips for used phone purchases, and current mobile network practices in 2026. It focuses on accurate, useful information without exaggerated claims.

IMEI stands for International Mobile Equipment Identity. It's a unique 15-digit number assigned to every mobile device that connects to cellular networks. This includes phones with physical SIM slots or eSIM capabilities, but not Wi-Fi only tablets.

IMEI vs MEID vs ESN: In 2026, IMEI is the standard identifier for GSM and most modern networks. MEID (14 hex digits) was used for older CDMA networks. ESN is an even older format from pre-2000s devices. When someone asks for your ESN, they may be using outdated terminology.

Here are standard methods to locate your IMEI number:

1. Universal Code: *#06#

   Open your phone dialer and type *#06#. The IMEI displays within seconds. This works on virtually all GSM devices manufactured since the 1990s.

2. Settings Menu (iOS & Android)

   iPhone: Settings → General → About → IMEI. You can long-press to copy.
   Android: Settings → About Phone → Status → IMEI information (exact path may vary by manufacturer).

3. Physical SIM Tray

   Many recent phones have the IMEI printed on the SIM tray. Remove the tray carefully (with phone powered off) to check.

4. Original Packaging

   The barcode sticker on your phone's original box typically shows the IMEI. It also appears on retail invoices from authorized sellers.

5. Find My Device Services

   Google Find My Device and Apple Find My show IMEI in device details for logged-in accounts.

6. Carrier Account Portal

   Mobile carriers often list IMEI numbers for active devices in account dashboards or apps.

IMEI numbers serve several practical purposes in mobile networks:

• Stolen Device Reporting: When a phone is reported stolen, carriers may add its IMEI to shared databases. Participating networks can then restrict service to that device.
• Network Compatibility Verification: Carriers check IMEI to confirm a device supports their network bands, VoLTE, and other features before activation.
• Warranty and Insurance: Manufacturers and insurance providers use IMEI to verify device eligibility, purchase date, and claim history.
• eSIM Activation: eSIM profiles are associated with specific IMEIs. Activation may fail if the IMEI is flagged in carrier systems.
• Law Enforcement Requests: With proper legal authorization, law enforcement can request carrier records showing when a specific IMEI connects to networks. IMEI alone does not provide real-time location tracking. Location data typically requires network records and lawful authorization depending on local regulations.
• Device Trade‑ins: When selling phones, trade-in programs check IMEI against databases to verify status and specifications.

What IMEI Does Not Do: IMEI itself does not provide real-time location tracking. Network-based location requires additional data and legal authorization. Claims about instant GPS tracking via IMEI are not accurate.

Verifying IMEI before purchasing a used device can help avoid issues. Here's a practical checklist:

1. Compare IMEI on Box vs Phone

   Dial *#06# and compare with the IMEI printed on the box. Mismatches may indicate stolen devices or unauthorized repairs.

2. Check Official Blacklist Portals

   Use official government or carrier resources where available: India's CEIR (ceir.gov.in), US carrier databases, or UK's CheckMEND. Free checks are available through official channels.

3. Verify Carrier Lock Status

   Some IMEI checking services can indicate if a device is still carrier-locked.

4. Check for Outstanding Financial Obligations

   In some regions, phones purchased on installment plans may be blacklisted if payments stop. Request documentation or check with the original carrier.

5. Test eSIM Functionality

   If possible, test activating a temporary eSIM profile to verify the IMEI is not blocked.

Devices with multiple cellular connections have multiple IMEIs. Here's how it works:

When checking IMEI status, it's advisable to verify both numbers if your device has them. Most carrier systems track both IMEIs for multi-SIM devices.

eSIM Transfer Considerations: Features like Apple's eSIM Quick Transfer use IMEI matching during the transfer process for security purposes.

Several misunderstandings about IMEI numbers persist. Here are accurate explanations:

• "You can track your phone via IMEI using apps": No legitimate app can track devices using IMEI alone. Official services like Google Find My Device or Apple Find My use account-based location services.
• "Police can instantly locate a phone using IMEI": Law enforcement access to location data requires proper legal authorization and involves network provider records, not real-time GPS via IMEI.
• "IMEI can be changed easily": Modern devices store IMEI in secure hardware components. Attempting to modify IMEI is illegal in many jurisdictions and typically indicates tampering.
• "IMEI number is same as serial number": Serial numbers are manufacturer-specific alphanumeric codes, while IMEI follows a global standardized format.
• "You need IMEI to unlock your phone daily": IMEI is used for network unlocking but not for daily device access like PIN or pattern.

Consider these recommendations for managing your device information:

Understanding your device's IMEI is a basic aspect of mobile ownership. With eSIM technology expanding and global carrier cooperation increasing, being informed about IMEI helps you make better decisions when buying, using, or reporting mobile devices.

Note: Free IMEI verification is available through official government and carrier portals. Verifying before purchase helps ensure the device can be activated on networks.