If you’re looking to troubleshoot an issue with your iPhone 6s, or just want to find out its unique identifier (IMEI number), here’s how to do it.

  1. Open the Settings app on your iPhone 6s.
  2. Tap General.
  3. Under “About Your iPhone,” tap “Serial Number.”
  4. Under “IMEI Number,” type in your phone’s serial number and press Enter/Return on your keyboard.
  5. If the IMEI number is not displayed, your phone may be locked and you will need to contact Apple support for assistance unlocking it. ..