What Is an ESN?

ESN stands for Electronic Serial Number. Every phone has a unique ESN, much like every person has a unique fingerprint. Carriers use ESNs to monitor account status and check for lost or stolen device reports.

How to Find Your ESN

Your device’s ESN can typically be found in one of these locations:

  • In your phone’s Settings menu (usually under “About Phone”)
  • On a label underneath or beside the battery
  • On the original packaging or receipt

ESN Format

  • Standard ESN: 11 digits
  • ESN HEX format: 8 digits
  • ESNs always contain the number “0” (zero), never the letter “O”

What Is a “Bad” ESN?

A “bad” ESN means the phone cannot be activated on a carrier’s network. This typically occurs when:

  • The previous owner has an overdue balance on their account
  • The device was reported lost or stolen
  • The account associated with the device is still active

How to Check If Your ESN Is Clean

Before selling your phone, it’s important to verify that your ESN is clear. Contact your carrier’s customer support using one of the numbers below (call from a different phone):

  • AT&T: 1-800-331-0500
  • Verizon: 1-800-922-0204
  • T-Mobile: 1-800-866-2453
  • Sprint: 1-888-211-4727
  • US Cellular: 1-888-944-9400

Ready to Sell Your Phone?

Once you’ve confirmed your ESN is clean, get an instant quote from TechPayout. We offer competitive prices, free shipping, and fast payment for your used electronics.