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How many phone numbers must I add for Two-Step Verification?

You must always have at least one phone number available, mobile or land line, to receive a one-time security verification code, and you can add a total of five phone numbers.

We recommend you add more than one phone number for several reasons:

• If you travel with a different SIM card or phone number
• If you travel and have access to a land line or mobile phone number that you trust at your destination, we recommend adding that phone number to your Security Settings, before you leave
• To make sure you can access your accounts, no matter where you are
• When your primary phone is not nearby
• If your primary phone is lost or not working

To view, update and add phone numbers to receive one-time security codes, go to Security Settings. 

Important: To update or add additional phone numbers in your Security Settings, you're required to have access to one of the phone numbers you've previously verified to receive a one-time security code.