Backup codes
Backup codes are an accessible option for users who do not have access to a phone. However, backup codes are the least secure option for two-factor authentication. Backup codes must be printed or written down which makes them more vulnerable to theft and phishing.
How to set up backup codes
If you select this less secure option, Login.gov will generate a set of ten codes. After you sign in with your username and password, you will be prompted for a code. Each code may be used only once.
When the tenth code has been used you will be prompted to download a new list. Treat your recovery codes with the same level of care as you would your password.