While working at AT&T Wireless in Customer Service, a frequently asked question was how to find the IMEI on the LG Nexus 5 phones so I am posting it here so that you can do it as well.
To do so, try entering the following characters into the LG Nexus 5 phone.
Please note that you need to enter this in the dialing area as if you were making a phone call so remember to launch your LG Nexus 5 phone’s dialing app.
LG Phones Tested
* LG 800 (Tested Okay)
* LG Nexus 5 (Tested Okay)
* LG L41C (Failed/Not Supported)
Non LG Phones Tested
* Motorola Nexus 6 (Tested Okay)