<p>With two-step authentication, a second layer protects your Yahoo! Mail account from suspicious log-in attempts.</p><h3>How Secure Is Your Email at Yahoo!?</h3><p>Your <a href="https://www.lifewire.com/yahoo-free-email-service-1174437" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">Yahoo! Mail</a> account is as secure as your password for it. Yahoo! checks not only the password when somebody attempts to log in to your account; it also looks at the location and computer whence the attempt is made. If one looks suspicious (say, a device you&#39;ve never used before), Yahoo! Mail can require more than merely the password—if you have two-step authentication enabled.</p><p>In that case, a second step is required for logging in, either entering a code sent to your mobile phone or answering security questions. (You can also turn off the latter and require mobile phone verification.) Your Yahoo! Mail account is then as secure as your password and access to your mobile phone.</p><p>(For a similar degree of security, <a href="https://www.lifewire.com/access-key-log-in-yahoo-1174444" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="2">Yahoo! Mail also offers Access Key log-on</a> via a mobile app.)</p><h3>Protect Your Yahoo! Mail Account with 2-Step Authentication</h3><p>To add a second layer of authentication for suspicious log-in attempts (from a new country, for example) to your Yahoo! Mail account:</p><ol><li>Hover the mouse cursor over your name or icon in the top Yahoo! Mail navigation bar.</li><li>Select <em>Account Info</em> from the menu that appears.</li><li>If prompted:<ol><li>Type your Yahoo! Mail password under <em>Password</em>.</li><li>Click <em>Sign In</em>.</li></ol></li><li>Follow the <em>Set up your second sign-in verification</em> link under <em>Sign-In and Security</em>.</li><li>Make sure <em>Check this box to turn on the second sign-in verification</em> is checked under <em>Further Protect Your Account</em>.</li><li>If you already have a mobile phone number associated with your account:<ol><li>Click <em>Use Current Phone</em> to use it for two-step authentication</li><li>Or, click <em>Use New Phone</em> to use a different phone number.<ul><li>Note that the form on this page may not allow you to enter phone numbers in all countries to which Yahoo! can actually deliver verification codes. (You can add those mobile numbers on your account page; see below.)</li></ul></li></ol></li><li>If you have not yet set up a mobile phone number or chose <em>Use New Phone</em>:<ol><li>Enter your phone number under <em>Second Sign-In Verification Setup: Add Mobile Phone</em>.</li><li>Click <em>Receive SMS</em>.</li></ol></li><li>Type the <a data-inlink="f4xZByQK4Wg6Qhd2LSgV2Q&#61;&#61;" href="https://www.lifewire.com/protect-outlook-account-1170661" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="3">verification code</a> received at the number under <em>Enter code : (</em>the code is not case-sensitive).</li><li>Click <em>Verify Code</em>.</li><li>Choose <em>Use only my mobile phone number for verification </em>under <em>Your second sign-in verification is turned on </em>to require the use of SMS text message verification or <em>Use either my security question or mobile phone number for verification </em>to allow two-step authentication with password and security question.</li></ol><p>Note that two-step authentication will not apply to Yahoo! Mail accessed <a href="https://www.lifewire.com/access-yahoo-mail-account-via-pop-1170876" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="4">via POP</a>, <a href="https://www.lifewire.com/what-are-yahoo-mail-imap-settings-1170872" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="5">on mobile devices, or IMAP</a>; for these, you can <a href="https://www.lifewire.com/manage-app-passwords-imap-pop-yahoo-1174448" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="6">create application-specific passwords</a>.</p><h3>Add a Mobile Number Not Recognized on the 2-Step Verification Form </h3><p>To set up a new mobile phone number for recovering access to Yahoo! Mail:</p><ul><li>Click your name or avatar in the top Yahoo! Mail navigation bar.</li><li>Select <em>Account Info</em> from the menu that shows.</li><li>Follow the <em>Update password-reset info</em> link under <em>Sign-In and Security</em>.</li><li>Click <em>Add another</em> under <em>Mobile Numbers</em>.</li><li>Enter your mobile phone number.<ul><li>Click the country code to pick a different one.</li></ul></li><li>Click <em>Save</em>.</li></ul>