You can choose to authenticate your Office 365 logins by having a 6-digit code texted to your cell.
Choosing authentication by text
1. Choose Authentication phone by clicking on the drop-down arrow and clicking on your choice.
2. Select your country or region and then fill in the phone number (without the 1 and without spaces or dashes). Choose to have a code sent to you, or to receive a call.
3. When you receive the text, enter the verification code in the indicated field, then press the Verify button.
4. Click the Done button on the window that pops up. Please note that you will have to create app passwords for some applications, such as Outlook, Apple Mail and Microsoft Office. Click here for more instructions.
5. The next time you sign into Office 365, you'll be prompted to enter the code that is sent to you. Enter your code and press the Sign in button.