Any device containing GSM cellular access functionality from the GSM family of standards, e.g., phones, smartphones, modems, dongles, tablets, PCs, IoT devices, payment terminals and vehicles. All must include an IMEI number generated from a GSMA-issued TAC code.

A Type Allocation Code (TAC) is an 8-digit number for 3GPP devices that identifies the make and model – which is why different device models require different TAC. Manufacturers use TAC to create a unique number that identifies individual mobile devices, known as the International Mobile Equipment Identity (IMEI). The IMEI is embedded into the device at the time of manufacture so it cannot be modified.

The purpose of an IMEI number is to identify a specific mobile device, not just its make and model. Crucially, it enables the network operator to accurately identify the device before allowing it to access the network. Without knowing the model and its capabilities, including band profiles, proper interaction between the network and device can’t be ensured. The device make and model are identified from the TAC component of the IMEI

First, you need a TAC number, as you can’t create an IMEI without one. So, register for a TAC Allocation account with the GSMA, then apply for a TAC code. If you are entirely new to the process, we strongly advise you to download and read our TAC Training Modules here.

The mobile industry appointed the GSMA as the Global Decimal Administrator (GDA) for 3GPP devices and multi-mode 3GPP/3GPP2 compliant devices. The GSMA’s role is to ensure TAC are allocated in compliance with standards, industry agreed practice and worldwide regulatory requirements.

• Enables devices to operate globally on mobile networks
• Maintains efficient network operations 
• Enables devices to provide services 
• Allows identification of counterfeit and stolen devices, so fraudulent insurance claims and laundering can be prevented

Only GSMA-appointed reporting bodies can review and approve TAC applications in support of the scheme’s rules. Current GSMA reporting bodies are:

• TuV SuD formally (BABT)
• Telecommunications Terminal Testing & Approval Forum (TAF)
• Cellular Telecommunications & Internet Association (CTIA)
• Telecommunications Industry Association (TIA) – multi-mode devices only

After obtaining a TAC from the GSMA, it is the TAC holder’s responsibility to generate the remaining digits to complete the unique IMEI number every mobile device requires. GSMA Training Module One details the rules as outlined in GSMA PRD TS.06.

No. TAC must uniquely identify a device model and can only be allocated from the central GSMA source. False TAC and/or IMEIs are not permitted by the industry. A false IMEI may render your device inoperable, cause confiscation of your devices by authorities and/or invite legal action from the wireless industry.

You must not implement an IMEI without the use of an officially allocated TAC from the GSMA. Once you have been allocated a TAC for your device model, you may generate up to a million IMEI numbers from that TAC and incorporate them into the devices of that model only. A false IMEI may render your device inoperable, cause confiscation of your devices by authorities and/or invite legal action from the wireless industry.

No. The purpose of a TAC code is to identify a device model. Therefore, the same TAC cannot be used for different device models.

No. Once a device model has been allocated a TAC, it is permanently recorded in the GSMA Device Database while it is active in the market. Using a TAC from a previous model will render your device inoperable, cause confiscation of your devices by authorities and invite legal action from the wireless industry.

No, neither the brand name nor model name can be changed – correcting typos is allowed but not fundamental name changes. In circumstances where a name change is required, a completely new TAC application is necessary.

The GSMA’s Terminal Steering Group is made up of mobile network operators and device manufacturers from around the world. Together, they maintain and manage the rules for TAC allocation.