Facebook search by phone number gives you the option to search for friends using their mobile number. Keep in mind that if your friend(s) has decided to keep their mobile number private, you will not be able to find them.
To do this, simply type in the mobile number in the search box. If your friend’s number is public, you should be able to see their profile in the search results.
If you in turn wants to be visible to friends upon Facebook mobile number search, ensure that you keep your cell phone number public.
Where to activate Facebook search by phone number
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