Does IMEI Change with SIM Card?

No, the IMEI (International Mobile Equipment Identity) does not change with the SIM card. The IMEI is a unique identifier assigned to a mobile device such as a phone or tablet. It is a permanent identifier that remains the same throughout the lifetime of the device, regardless of the SIM card being used.

What is IMEI?

IMEI, or International Mobile Equipment Identity, is a unique 15-digit number assigned to every mobile device. It serves as a tracking tool for lost or stolen mobile phones. However, can you change the IMEI number of your phone? It is important to note that an IMEI number cannot be changed or replaced, unlike a SIM card. While it is possible to modify an IMEI number in certain circumstances, this practice is often illegal in many countries, including the US, the UK, and the EU.

In fact, changing an IMEI number can lead to legal implications. It is best for users to check their respective countries’ changing process policies before proceeding. Accessing the IMEI number is relatively easy, either by unveiling the battery of the device or dialing *#06# on the dial pad.

What is a SIM card?

A SIM card stands for Subscriber Identity Module. It is a small, removable card that holds an authentication key which identifies a subscriber on a mobile network. On the other hand, IMEI stands for International Mobile Equipment Identity which is a unique identification number assigned to each mobile device. The IMEI structure consists of a 15-digit unique number used to identify each device on a wireless network.

The IMEI is flashed to the chipsets on the device when it is manufactured and is usually found inside the phone’s internal read-only memory. Changing a device’s IMEI is illegal in many countries, including the US, and can result in severe legal consequences. Despite this, some circumstances may allow for the change of an IMEI number, but it is important to check if the process is allowed in your country before proceeding.

The Basics of IMEI

IMEI stands for International Mobile Equipment Identity, which is a unique code assigned to each mobile device. It helps in tracking and identifying a device in case it is lost or stolen. The code consists of 15 digits and is printed on the backside of the phone as well as on the packaging box. However, unlike SIM cards, IMEI cannot be changed or replaced.

It is illegal to modify an IMEI number in many countries, including the US, UK, and EU. To access the IMEI number, one can either check the battery compartment, dial *#06# on the dial pad, or check the packaging box. It is important to store the IMEI number safely as it may be required in times of emergency.

Can Changing SIM Cards Alter the IMEI?

No, changing SIM cards does not alter the IMEI number. The IMEI code is manufactured and flashed onto the device’s chipsets, which remain the same regardless of the SIM card used. However, it is essential to note that the SIM card plays a crucial role in connecting to the network and making calls.

Therefore, it is important to use a compatible SIM card with the device to ensure proper functioning. Moreover, replacing a damaged SIM slot does not change the IMEI number. The slot is independent of the antenna/radio and does not affect the code. However, it is illegal to change the IMEI number of a device in many countries.

IMEI structure and format

IMEI structure and format: The International Mobile Equipment Identity (IMEI) is a unique numerical identifier for every mobile device. A standard IMEI number is a 14 digit string with an additional 15th check digit for verifying the entire string. There is also a 16 digit variation that includes information on the devices software version known as the IMEISV.

The IMEI appears in the format AA-BBBBBB-CCCCCC-D. The sections labeled A and B are known as the Type Allocation Code (TAC). The TAC portion of the IMEI identifies the manufacturer and model of the device. The six C digits represent your devices unique serial number, and the D portion of the IMEI is a check digit that ensures the IMEI meets the Allocation and Approval Guidelines.

How IMEI is assigned to mobile devices

The GSMA assigns TACs to manufacturers who then allocate unique serial numbers for each device. The device manufacturer then calculates the check digit using the Luhn Algorithm, and the result is the complete IMEI number. The IMEI number is then added to the device’s firmware, and it also appears on the device’s packaging label.

Can changing SIM cards alter the IMEI?

No, changing a SIM card does not alter the IMEI of a device. The IMEI is physically written into the device’s firmware and is separate from the SIM card. While changing a SIM card can affect the device’s functionality, the IMEI is unaffected.

Legal considerations and IMEI/SIM card changes

Changing an IMEI is illegal in many countries as it is considered phone reprogramming, facilitating fraud, and tampering with the device. Even possessing equipment that can change an IMEI is considered an offense. SIM card changes, however, are legal as it is a user’s prerogative to switch networks or phones. However, tampering with a SIM card to bypass network restrictions is illegal.


IMEI and SIM cards play different roles in mobile devices. The IMEI is a unique identifier that distinguishes each mobile device, while SIM cards store network-specific and personal information that enables users to access a network. Changing SIM cards does not affect an IMEI, and changing an IMEI is illegal in many countries. It is important for users to understand the roles of the IMEI and SIM cards to avoid legal issues and ensure a smooth mobile experience.


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