![Add a cell phone number to Facebook - Step 1](i/add-your-cell-phone-to-facebook-step-1.png)
While you can use your Facebook account without a cell phone number associated with it, you'll quickly face limits. Besides, tying your cell phone to your account also means that you can secure it more effectively - for example, by enabling Facebook's "Login Approvals", a feature that prevents someone from logging into your account unless they enter a six-digit code, generated through your mobile Facebook app, or sent as SMS text to your phone.
![Add a cell phone number to Facebook - Step 2](i/add-your-cell-phone-to-facebook-step-2.png)
Once logged in, click on the arrow in the top right corner and select Settings.
![Add a cell phone number to Facebook - Step 3](i/add-your-cell-phone-to-facebook-step-3.png)
On the next screen, select the "Mobile" options in the left column.
![Add a cell phone number to Facebook - Step 4](i/add-your-cell-phone-to-facebook-step-4.png)
If you already have a cell phone in your account (like I do, see screenshot), click on the Add another mobile phone number link. Otherwise, click on the lone Add a phone link. Facebook lets you add multiple numbers to the same account (and even have the same phone number for different accounts).
![Add a cell phone number to Facebook - Step 5](i/add-your-cell-phone-to-facebook-step-5.png)
Choose your country (used for the country code), and type your phone number, including area code. Click Continue: Facebook will send you a confirmation code as SMS text message. Once you receive it, type it in the text box and click Confirm. If you see privacy options, do read them carefully: one of them gives Facebook permission to share your phone number with friends!