Getting an apartment in San Francisco is a competitive nightmare, which is why I was excited to find that the landlord I had been texting with to set up an apartment viewing just happened to be friends with another good friend of mine. She didn't tell me, and we aren't Facebook friends: I found out because she has her phone number stored on the social network. When we started coordinating apartment viewing times, my phone automatically pulled in her profile pic and linked to her account.
Image credit: Pexels
I admittedly thought it was a little creepy to send a "I just saw you're friends with my friend" email, but I did, and consequently got the (pretty bad-arse) apartment. #NoRegrets, although she might have some. I doubt sharing her Facebook account with randoms looking at her apartment was intentional. By having your phone number on the site, you're letting anyone who has your number (be it the plumber or that person you met at a bar last night) find your profile.
While I discovered my landlord's friend list via a few simple texts, the feature also works somewhat in reverse, allowing people to figure out your phone number.
Hacker Noon points out that whenever you have "who can look me up by phone" set to public in your Facebook privacy settings, then your phone number is essentially public as well. The setting defaults to public, in general, and your privacy setting for "Who can look me up" also overrides what you have set for the phone number. So if you have your privacy settings set so anyone can look you up, then anyone can also see your phone number.
When it comes to adding your number to Facebook, your only privacy options, in fact, are sharing that number with Everyone, Friends of Friends, and Friends. There isn't an "only me" option.
Screenshot: Facebook/ E.Price
And you might not realise Facebook even has your number: The app repeatedly asks you to confirm your number for security reasons. It's easy for you to have added it during one of those "confirmations" without realising you were inadvertently passing your number out to the masses.
In an article explaining how Facebook figure out everyone you've met, Gizmodo notes that "The shadow profiles, like the People You May Know system they feed into, can't be turned off or opted out of. The one thing you can do to impede Facebook's contacts-based connections is, through its Privacy Settings menu, keep people from finding your profile by searching your phone number or email address."
If you want to remove your number from Facebook (or see if it's there in the first place) you can do so by pressing the down arrow at the top right side of your profile page and then picking Settings from the drop-down menu. From there, select General from the side menu and then Contact to see if you have a number listed. You can adjust who can search for you by selecting Privacy from the menu on the left side of the page, and then adjust the setting for "Who can look you up by phone number".