An ESN (Electronic Serial Number) is a unique identifier tied to all cellular devices. ESNs can be found in a few different formats. The most common is the IMEI (International Mobile Equipment Identity). However, some older mobile devices have a MEID (Mobile Equipment Identifier).
No two devices should ever have the same ESN / IMEI, and reviewing this number is one of the most important steps in Swappa's listing review process. Thus, it's crucial to ensure that you provide the proper ESN when creating a listing on Swappa.
Check the status of your phone with Swappa’s free ESN check
Learn more on the Swappa Blog: How to find your phone’s IMEI / ESN