TAC Codes Explained: How to Identify Any Phone by Its IMEI

What Is a TAC Code?

A TAC (Type Allocation Code) is the first 8 digits of an IMEI number. It is essentially a product identifier for mobile devices, allocated by the GSMA to manufacturers when they register new device models. Before 2004, the TAC was only 6 digits (with a 2-digit FAC — Final Assembly Code — indicating the factory). The GSMA restructured the system, expanding the TAC to 8 digits and absorbing the FAC.

The TAC tells you what the device is, while the following 6 digits form the serial number identifying which specific unit, and the final digit is a Luhn check digit that validates the whole sequence. For example, in the IMEI 35 846710 123456 7, the first 8 digits (35846710) are the TAC, 123456 is the serial, and 7 is the check digit.

How TAC Codes Are Allocated

The allocation process works through a hierarchy managed by the GSMA. A manufacturer applies to the GSMA for a TAC when developing a new device model. The GSMA assigns a unique 8-digit TAC through a Reporting Body — BABT in the UK, PTCRB in the US, TCA in Australia, or MSAI in India. The manufacturer then uses that TAC as the prefix for all IMEIs produced for that model. Each TAC can generate up to 1 million unique devices (6-digit serial = 000000–999999).

Large manufacturers like Apple or Samsung have hundreds of TACs — one for each model variant, carrier version, and regional SKU. A single phone model like the iPhone 15 Pro might have 10+ TACs covering different storage sizes, carrier configurations, and markets.

How to Decode a TAC Code

The first two digits of a TAC historically indicated which reporting body allocated it. Prefixes 01-02 correspond to PTCRB (US), 35-44 to BABT (UK), 45-49 to TCA (Australia), 50-59 to various Asian reporting bodies, and 86-91 to Chinese TAC allocations. Since the 2004 restructuring, these prefixes are less rigidly tied to reporting bodies, but patterns still hold: Apple TACs often start with 35, Samsung frequently uses 35 or 86, and Chinese manufacturers typically start with 86-91.

The full 8-digit TAC maps to a specific manufacturer and model. There is no mathematical formula to decode it — you need a database lookup. Use our IMEI generator and TAC lookup to decode any TAC code instantly.

Common TAC Prefixes by Manufacturer

While TACs are not assigned by manufacturer prefix, patterns emerge from allocation history. Apple dominates the 35 prefix range — for example, 35397210 maps to iPhone 14 and 35695613 to iPhone 15 Pro. Samsung uses mixed prefixes: 35462911 for Galaxy S23 and 86795603 for Galaxy A54. Xiaomi and Redmi often appear under the 86 prefix (e.g., 86988505 for Redmi Note 12). Google Pixel devices typically use 35 prefixes (35455117 for Pixel 7), while Huawei dominates the 86 range (86670903 for P40 Pro).

TAC in Real-World Applications

TAC codes power several critical systems. Carriers use TAC databases to control which devices can connect to their networks — when your phone registers on a cell tower, the network reads the IMEI, extracts the TAC, and checks if the device is certified and supports required technologies like VoLTE or 5G NR. The GSMA IMEI Database uses TACs to categorize blacklisted devices for theft prevention. Checking the TAC against the seller's claimed model is the fastest way to detect counterfeits — if someone sells you an "iPhone 15 Pro" but the TAC maps to a generic feature phone, it is a confirmed counterfeit.

TAC for Enterprise and Analytics

Enterprise MDM (Mobile Device Management) systems use TAC lookups to enforce device policies. IT departments can set rules like "only allow devices with TACs matching approved models" or segment policies by manufacturer. Mobile analytics platforms aggregate TAC data to understand device market share by region, technology adoption rates (5G-capable devices), and manufacturer distribution on specific networks. This data helps businesses make informed decisions about device support, app optimization, and market strategy.

TAC for Testing and Development

If you are building telecom software, MDM systems, or mobile analytics tools, you need test IMEI numbers with valid TACs. Using production IMEIs creates legal and privacy issues. Use a random IMEI generator to create test data with valid TAC structures, validate your IMEI parsing logic against known TAC-to-model mappings, and test edge cases like dual-SIM devices (two IMEIs), eSIM devices, and legacy 14-digit MEIDs. For other testing needs, check out our MAC address generator for network testing or our IBAN generator for financial system testing.

The Future of TAC and IMEI

The TAC system is evolving as technology changes. As physical SIM cards give way to eSIM and embedded iSIM, the IMEI/TAC system remains relevant — it identifies the device, not the SIM. However, the explosion of IoT devices is putting pressure on the IMEI numbering space. The current TAC structure supports approximately 100 million unique TACs × 1 million devices each, but IoT growth may require restructuring. Newer standards also include the IMEISV (IMEI Software Version), a 16-digit identifier that appends a 2-digit software version number, helping networks identify not just the hardware model but also the firmware version — critical for security patch management.