Electronic Serial Number


Electronic Serial Number (ESN) is a unique identification number embedded by manufacturers in mobile devices. This number is utilized by telecommunication companies to authenticate the identity of a device on their network. ESN is often used for preventing mobile theft, as well as, for device activation or deactivation.


The phonetic transcription of “Electronic Serial Number” in the International Phonetic Alphabet is:Electronic: /ɪˌlɛkˈtrɑːnɪk/Serial: /ˈsɪriəl/Number: /ˈnʌmbər/

Key Takeaways

  1. The Electronic Serial Number (ESN) is a unique identification number embedded by the manufacturer on a wireless device. It serves the purpose of preventing fraud by ensuring that the device is legitimate.
  2. ESNs were primarily used in the 1980s and 1990s in CDMA and AMPS mobile phones. However, the use of ESNs has been largely replaced by MEID and IMEI numbers in newer devices.
  3. ESNs can be utilized by service providers to block lost or stolen devices from accessing the network. Likewise, they can be used to deactivate devices that have unpaid bills linked to them.


The Electronic Serial Number (ESN) is a unique identifier for a mobile device, primarily used in CDMA (Code Division Multiple Access) technology. Its importance lies in the role it plays in the prevention of fraud and theft in the mobile communication industry, as it allows wireless carriers to have a list of all the devices manufactured for its network. Accurately identifying a device ensures the authenticity of the device and helps in blocking any false usage or activation. Furthermore, it aids in the process of tracking lost or stolen devices, guaranteeing customer security and data privacy. Overall, the ESN is an essential part of maintaining network security, integrity, and operational efficiency in the mobile telecommunications sector.


The Electronic Serial Number (ESN) serves as a unique identifier for a piece of hardware, particularly mobile phones. This unique code holds high importance because it is primarily used for mobile equipment identification, ensuring secure communication. It facilitates the tracking of mobile devices, and service providers use it to authenticate the user’s device, thus reducing the risk of fraud. When a mobile device connects to a network, the ESN is transmitted to permit the relevant network to validate the device.Moreover, the ESN also plays a crucial role whenever a user wishes to change service providers or sell their device. The ESN allows the new provider to verify whether the device has been reported as stolen or is linked with any unpaid bills. Additionally, it is useful in instances of device theft, where tracking becomes possible due to the unique ESN. Thus, the Electronic Serial Number adds a layer of protection for both the service provider and the device owner, making it an important aspect of cellular technology.


1. Mobile Phones: In mobile phones, Electronic Serial Number (ESN) is a unique identification number that is built into the phone when it is manufactured. The ESN is automatically transmitted to the carrier when a call is made to help with billing and monitoring for fraud.2. Satellite TV Receivers: Satellite providers such as DISH Network and DirecTV use Electronic Serial Numbers in their receivers to control and monitor access to their broadcast signals. These ESNs help ensure that only authorized users can receive the satellite broadcast signal.3. Cellular Data Cards: Cellular data cards also use ESNs to authenticate and connect with the cellular data network. The network can refuse connection if an ESN is not recognized, which helps prevent unauthorized use of the network.

Frequently Asked Questions(FAQ)

Q: What is an Electronic Serial Number (ESN)?A: An Electronic Serial Number (ESN) is a unique identification number embedded by the manufacturer in a wireless communications device. It is used by mobile carriers to identify valid devices, prevent theft, and deter fraudulent cellular service use.Q: Where can I find my device’s ESN?A: The ESN is usually printed on the device’s label underneath the battery. You can also often find it in the device’s settings or by dialing a specific code that varies depending on the device’s model.Q: How does an ESN work?A: When you try to connect your device to a mobile network, the carrier checks the ESN to ensure the device hasn’t been reported as lost, stolen, or connected with fraudulent activities. If the ESN is cleared, the device can connect to the network.Q: Is an ESN the same as an IMEI?A: While ESN and IMEI both serve as identifying numbers for mobile devices, they are not the same. An IMEI is longer, has more information embedded, and is used more frequently worldwide. However, both numbers are checked in similar manners by carriers for device validity.Q: Can an ESN be changed?A: An ESN is hardcoded into the device by the manufacturer, so it cannot and should not be changed. Altering the ESN is illegal in many locations because it can be used to evade carrier blacklist databases.Q: What is an ESN swap?A: An ESN swap, also known as an ESN change, is when a carrier assigns your service from an old device’s ESN to a new device’s ESN. This is a legitimate and commonly provided service by carriers when a customer changes their phone.Q: What should I do if my device with my ESN is lost or stolen?A: If your device is lost or stolen, you should notify your service provider immediately. They can blacklist the ESN of the device to prevent others from activating it on their network.

Related Finance Terms

  • Mobile Equipment Identifier (MEID)
  • International Mobile Equipment Identity (IMEI)
  • Mobile Identification Number (MIN)
  • Subscriber Identity Module (SIM)
  • Global System for Mobile Communications (GSM)

Sources for More Information


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