When you first log into your FB account, you'll be able to Sync all Contacts, or Sync with Existing Contacts. The phone will automatically merge contacts it recognizes as being the same (if it's the same first and last name or you have an email attached to them or even if they have their phone number in their info). However, sometimes it's wonky. If you're having a prob, DL an app called SyncMyPix. It's a free app, but they do have a $1 donate version (which I always recommend, keep supporting the devs, you keep getting great apps). It may not sync all of them, but you'll be able to manually go through the ones it misses. Hope this helps, and let us know how things work out.