How to Make Your Signal Chats as Secure as Possible Enable Registration Lock to Protect Your Signal Account Your Signal account is tied to your phone number, with no need for a password at all. When you first register for Signal (or re-register a device at a later stage), Signal will verify who you are by sending a code to your number. Enter the code to prove you are who you say you are and you’re good to go. But what happens if someone gets access to your phone number? While this might seem like an unlikely eventuality, it’s within the realm of possibility. Someone could steal your smartphone’s SIM card or fool your phone service provider into transferring your number to a new SIM using social engineering techniques.