Wireless Carriers

This article will help you in finding the Account Number and PIN needed for porting out from many major mobile carriers in the US.

Verizon

Account Number: It can be found on any bill or invoice that you may have or in your online account by going to "Account Overview" where it is listed at the top, without any dashes.
PIN: It can be generated by dialing #PORT from your phone. If the My Verizon app is installed on your device, you'll be directed to the Number Transfer PIN screen in the app. If the My Verizon app is not installed, you'll be directed to the Number Transfer PIN screen on your mobile browser.
Note: You can also request a Number Transfer PIN online in My Verizon. To request a Number Transfer PIN online, go to the Number Transfer PIN page and click or tap "Generate PIN". Your PIN and Account Number will display on the screen. The Number Transfer PIN is valid for 7 days.

AT&T

Account number: It can be found in the upper right corner on any bill or invoice that you may have, in your online account. For bundled bills, the account number will be a 12-digit number under your wireless account summary.
PIN: It is usually the last four digits of your telephone number. It is not on your bill, invoice, or online account. You can call AT&T at +1 (800) 331-0500. For bundled bills, the account number will be a 12-digit number under your wireless account summary. Also, only for bundled bills, call AT&T customer service for a 4-digit PIN.