Log in Using a Phone Callback for Two-Step Login
How to use a phone call to authenticate with Two-Step Login
This article applies to: Two-Step Login
Starting November 4, 2025, Cornell will begin disabling the Duo Phone Call and Duo SMS Passcode methods.
If you have been regularly using either of these methods, transition to using the Duo Mobile app, a USB security key, or a hardware token as soon as possible to avoid losing access to Cornell websites and systems.
Affected campus populations will be notified by direct email about when this change will affect their accounts. To learn more, visit Important Two-Step Login (Duo) Changes, Starting August 2025.
If you have been regularly using either of these methods, transition to using the Duo Mobile app, a USB security key, or a hardware token as soon as possible to avoid losing access to Cornell websites and systems.
Affected campus populations will be notified by direct email about when this change will affect their accounts. To learn more, visit Important Two-Step Login (Duo) Changes, Starting August 2025.
With the Phone Callback method, Two-Step Login calls you on your mobile phone or landline.
To authenticate:
- When you're prompted with the Two-Step Login screen, click Call Me.
- Answer the phone call.
- When you hear the automated "Welcome to Cornell Two-Step Login" greeting, press the requested number key on your phone to authenticate. To find the number:
- Press the number shown in the authentication prompt on your computer screen:
or - For a phone with Caller ID, the number you need to press appears as the last digit of the incoming phone number. For example, if Caller ID displays
607-253-3333, press 3 on your phone keypad to log in;
or - Listen to the phone message and press the requested number on your phone.
- Press the number shown in the authentication prompt on your computer screen:
Voice/SMS calls from Duo usually display a Caller ID from an on-campus Cornell phone number. Occasionally a Duo call may come from an off-campus phone number elsewhere in the United States. If you just tried to log in and are expecting a Duo call, the call is probably legitimate.
If you think this is a fraudulent login attempt, press # to report it to a security engineer.
For more information, see Duo Security's Guide to Two-Factor Authentication.
Support Contact:
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