Comparison
IMEI vs TAC vs Serial Number
IMEI, TAC, and serial number are three identifiers used for mobile devices. They are closely related but serve distinct purposes. Here's how to tell them apart.
Updated March 2026 Β· 4 min read
Comparison Table
| Criteria | IMEI | TAC | Serial Number |
|---|---|---|---|
| Full name | International Mobile Equipment Identity | Type Allocation Code | Serial Number (S/N) |
| Format | 15 digits | 8 digits | Variable (alphanumeric) |
| Identifies | A unique device | A device model | A unique device (manufacturer) |
| Assigned by | GSMA | GSMA | Manufacturer (Samsung, Appleβ¦) |
| Uniqueness | Worldwide, unique per SIM slot | Shared by all devices of the same model | Unique per manufacturer |
| Relationship | Contains TAC + SNR + check digit | First 8 digits of the IMEI | Independent from IMEI |
| Mobile network | Used by operators to identify the UE | Used to detect network capabilities | Not used by the network |
| Example | 35391012 345678 4 | 35391012 | R58T30BFXYZ |
How Are They Related?
The TAC is a subset of the IMEI. The manufacturer serial number is a separate identifier, assigned independently.
IMEI Structure (15 digits)
TAC
8 digits
35391012
SNR
6 digits
345678
CD
1
4
Manufacturer Serial Number: R58T30BFXYZ β independent system
When to Use Each Identifier
IM
IMEI. To identify a specific device
- Report a theft to your carrier or law enforcement
- Check if a second-hand device is blacklisted
- Activate a mobile plan or register a device on a network
- Diagnose a network issue on a specific UE
TC
TAC. To identify a device model
- Look up network specs for a model (bands, CA, MIMO)
- Identify devices by model in network traces
- Verify device compatibility with a network
- Plan network deployment based on the device fleet
SN
Serial Number. For manufacturer tracking
- Check warranty status with the manufacturer
- Request a replacement or service repair
- Identify exact configuration (storage, color, version)
- Track a device in an inventory management system (MDM)
Frequently Asked Questions
Can you find an IMEI from a TAC?
No. The TAC identifies a device model, not an individual unit. You would need the 6-digit SNR and the check digit to reconstruct a complete IMEI.
Does the serial number change after a factory reset?
No. The manufacturer serial number is hard-coded during production. A factory reset does not affect the serial number or the IMEI.
Can a device have multiple IMEIs?
Yes. Dual SIM smartphones have two IMEIs (one per SIM slot). Some 5G devices with eSIM can have up to 3 IMEIs.
Is the TAC the same for all variants of a model?
No. The same model can have different TACs depending on the region (EU, US, Asia), storage (128 GB vs 256 GB), or connectivity (4G vs 5G, mmWave vs sub-6).
Is the Apple serial number the same as the IMEI?
No. Apple uses a proprietary serial number (alphanumeric format, e.g., DNPX...) that is distinct from the IMEI (15 digits). Both identify the device but in different systems.
How can I look up a TAC for free?
Use our free TAC Lookup tool on HiCellTek. Enter the first 8 digits of an IMEI to identify the brand, model, and chipset of the device.
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Look Up an IMEI or TAC Now
Enter an IMEI number or the first 8 TAC digits to instantly identify the brand, model, and chipset.