What Is a Burner Phone and Are They Really Untraceable?

Two men shopping at a SIM Local prepaid wireless store. — Customers buy prepaid phones (aka burner phones) at London's Heathrow Airport. Jeffrey Greenberg/Universal Images Group via Getty Images

You may hear about them on the news: "The suspect used a burner phone to contact the family after the kidnapping." Or you have seen them at a convenience store. But what are burner phones? A burner phone is, quite plainly, a cheap phone that comes with prepaid minutes. These are simple devices that often resemble old flip phones, though they can have touchscreens and smart features as well. These burner phones come pre-loaded with a certain amount of call minutes or text messages, which can also be re-loaded when exhausted.

"People who want to remain private or anonymous for a variety of reasons, such as journalists, activists or people engaging in illegal activities, frequently use them," explains cyber expert Shanal Aggarwal via email. He currently serves as the chief commercial officer for the software and web development company TechAhead. "Other common users include those who want to keep their identity a secret."

But even if you pay cash for the prepaid mobile phone and minutes, it doesn't mean you're incognito. Cell phones can easily be tracked and mined for data by app developers, third-party advertisers and even local governments.

In the United States, legislative acts such as the Foreign Intelligence Surveillance Act and the infamous Patriot Act have given the federal and state governments great power when it comes to tracking and retrieving wireless communications. Ostensibly, these laws concern matters of national security, but they've been used as a pretense numerous times by law enforcement to surveil the lives of ordinary citizens. In most cases, the agencies invoking these acts aren't even required to obtain a formal search warrant. Some activist groups, such as the American Civil Liberties Union, consider this to be a violation of the Fourth Amendment of the Constitution.

More recently, law enforcement agencies have added a tool known as the "Stingray" to their arsenal. These devices have been suspected to be deployed during mass protests, including the Black Lives Matter movement demonstrations in 2020. The Stingray is essentially a small, temporary cell tower that inserts itself as a bottleneck between mobile phones and their networks.

If you are in range of a Stingray, then your phone will automatically connect to it as if it were a legitimate tower. You'll be able to use mobile data as normal, but things like calls, text messages and passwords may be covertly intercepted by the party that controls the antenna.

Private companies can also declare open season on your mobile data. When it comes to smartphone apps, you've probably given some permissions to access things like your location, contact list or microphone. Shady developers can then turn around and sell this data to advertisers and government entities as an underhanded way to make extra money.

Burner Phone Advantages

Normal cell phones usually require a carrier wireless plan, which comes with a contract that is tied to the user's legal name. This means that any data scraped from your cell phone can easily be tied to your identity. Prepaid cell phones add an extra layer of protection because they can usually be purchased with cash and with no contract required.

"Burner phones can be beneficial for keeping privacy and anonymity in certain situations, such as when dealing with sources as a journalist or while going to a new country where local SIM cards may be necessary," Aggarwal says. "In addition, the use of a burner phone for acts that are not considered illegal and the avoidance of the disclosure of personal information is helpful in maintaining one's anonymity."

To make sure that anonymity continues, users of these prepaid phones will often disconnect or "burn" the device after a certain amount of time. Or even throw it away. If anonymous calls are still needed, the phone is then replaced with a new pre-paid number. If a third party happens to be scraping the device for data, then this method ensures that their information stream will end when the phone is burned.

Burner Phone Disadvantages

Burner phones offer the strength of anonymity upon purchase, but otherwise they possess the same weaknesses as other phones. "While burner phones offer a higher level of anonymity compared to regular phones, they are not completely untraceable," Aggarwal says. "Burner phones can be traced by law enforcement agencies using various methods, such as call detail records (CDRs), location tracking, surveillance and Stingray devices."

If a third party has recordings of your phone calls and texts, then it's possible that they could identify you using contextual information or simply by the sound of your voice. Law enforcement agencies also possess voice recognition technology that can assist in matching a voice to its source. It's because of these ever-present surveillance methods that burning the phone every so often is important to staying anonymous.

"These methods can reveal information regarding calls made and received by the burner phone, such as the time of day, the length of time and the location. Law enforcement authorities have had some success in determining the identities of people using burner phones in several instances," says Aggarwal.

Of course, if you log into your Facebook or TikTok account from your burner phone, or buy some goods from Amazon, that will certainly blow your cover of anonymity.

Beyond the Burner: Other Secure Phone Methods

Burner phones work, but are just one type of gadget that can be used to boost your cybersecurity. They aren't infallible and they're best employed in conjunction with other methods.

"For instance, encrypted messaging applications like Signal offer end-to-end encryption, which means that the only people who can read the messages are the sender and the recipient; not even the app providers themselves can access the information," says Aggarwal. "In addition, making use of a virtual private network, often known as a VPN, can assist in preventing third parties from tracking your location data as well as the online activities that you participate in."

Piling methods of data abstraction on top of each other will go a long way toward maintaining anonymity. Still, it's important to remember that none of them are perfect. At the end of the day, data can be tracked. The best encryption has the potential to be broken and the only 100 percent secure form of communication is a face-to-face conversation with someone you trust.

Burner Phone Apps

In lieu of a physical burner phone, some people download a burner app on their smartphone. Instead of a prepaid phone providing the anonymity, the burner phone app generates a second phone number that can be used for calling and texting. However, there is usually a cost for this service.