How I Got a Truly Anonymous Signal Account

The messaging app Signal is described by security professionals as utilizing the gold standard of cryptography. Unlike many competitors, its default is end-to-end encryption — and on top of that, the app minimizes the amount of information it stores about users. This makes it a powerful communication tool for those seeking a private and secure means of chatting, whether it’s journalists and their sources, activists and human rights defenders, or just ordinary people who want to evade the rampant data-mining of Big Tech platforms.

Signal continues to introduce privacy-enhancing features such as usernames that can be used in lieu of phone numbers to chat with others — preventing others from finding you by searching for your phone number. But the app still requires users to provide a working phone number to be able to sign up in the first place.

For privacy-conscious individuals, this can be a problem.

In response to subpoena requests, Signal can reveal phone numbers. Relying on phone numbers has also led to security and account takeover incidents. Not to mention that the phone number requirement costs Signal more than $6 million annually to implement.

Signal insists on its site that phone numbers are a requirement for contact discovery and to stymie spam. (Signal did not respond to a request for comment). Other encrypted messaging platforms such as Session and Wire do not require phone numbers.

There are some ways around Signal’s phone number policy that involve obtaining a secondary number, such as using temporary SIM cards, virtual eSIMs, or virtual numbers. But these approaches involve jumping through hoops to set up anonymous payment measures to procure the secondary numbers. And sometimes they don’t work at all (that was my experience when I tried using a Google Voice number to sign up for Signal).

I wanted a way to get a Signal account without leaving any sort of payment trail — a free and anonymous alternative. And thus began my long and tedious journey of registering Signal with a pay phone.

Finding a Pay Phone

The first step was actually finding a pay phone, a task which is dismally daunting in 2024.

The Payphone Project lists around 750,000 pay phones, but after attempting to cross-check a sampling of the hundreds of alleged pay phones in my town with Google Street View and Google Earth satellite images, I came to the quick realization that the list was woefully outdated. Many of these phones no longer exist.

A Google Maps search for pay phones in my area brought up of a half-dozen pins. Using Street View, I found that four locations seemed to have something resembling a pay phone box. Trekking out to them, however, revealed that one no longer had a pay phone, though discoloration of the store façade revealed the precise spot the pay phone used to be; another pay phone looked like it had been the victim of a half-hearted arson attack; the third and fourth lacked dial tones.

Asking on a community subreddit resulted in suggestions that once again led me to places without any working pay phones, or posts berating me for needing a pay phone in 2024 and inquiring about the legality of the endeavors I wished to pursue which would necessitate pay phone usage.

Failing at finding a functional pay phone through a systemic approach, I resorted to brute opportunism — keeping my eyes peeled for pay phones as I went through the dull drudgery of a modern life made ever bleaker by the lack of public phone access.

A Working Pay Phone, That Is

I didn’t just need to find a working pay phone — no small feat in 2024. I also needed to find one able to receive incoming calls, so I could get Signal’s activation message.

On a recent visit to Tampa, where I travel annually to discuss security matters and set things on fire, I spotted a pay phone while leaving Busch Gardens. Picking up the receiver, I was delighted to hear the telephonic equivalent of a pulse: a dial tone.

Now that I had a phone with a dial tone, the next step was to test whether it could receive incoming calls. This is because Signal’s registration process requires a phone number that can either receive a text message or a verification call.

To test whether a pay phone can receive incoming calls, you need to know one thing: the pay phone’s own phone number. Some pay phones reveal their numbers on the phones themselves, but not always.

If the number isn’t listed on the phone — it wasn’t in this case — there’s a workaround that doesn’t involve a paper trail leading back to your cellphone. Use the pay phone to call what’s known as an ANAC (automatic number announcement circuit), which provides an ANI (automatic number identification) service. In other words, it’s a phone number you can call which then reads out the phone number you are calling from. Lists of ANAC numbers have been bantered about for years, though like pay phone lists, almost all are now defunct.

One stalwart ANAC number that has withstood the test of time for over 30 years, however, is 1-800-444-4444. Feel free to try it. Call the number, and it should read yours back to you.

Back at Busch Gardens, I rang up the ANAC and had a number read back to me. The next and final step was to test whether the number actually accepted incoming calls. Unfortunately, when I called the number the ANAC line had read back to me, I reached the Busch Gardens main line, asking me to enter my party’s extension. In other words, this wasn’t actually the pay phone’s number, it was just the general theme park number.

Days later, during a layover on my trip home from Tampa, I noticed a small bay of pay phones at a small regional airport. I repeated the above rigamarole, and lo and behold, when I called the pay phone’s number from the neighboring pay phone, I was able to answer and talk to myself.