Why Old Phones Don’t Work on Modern Cellular Networks

Landline Phone Technology Dates Back to the ’60s

If you find an old push-button telephone in a closet, you can probably still connect it to your landline and it’ll work just fine. That’s because these phones have used the dual-tone multi-frequency (DTMF) technology standard since 1963. In other words, that phone from the ’60s will still work with a modern telephone landline because they use the same technology.

(Before that, rotary telephones and some early push-button telephones used something called pulse dial signaling. They won’t work when plugged into a modern landline—not unless you buy a converter.)

Cellular Standards Are Quickly Changing

Cellular technology is very different. We’re not using a standard that dates back decades anymore. Instead, technology companies are regularly coming out with new standards: 5G was first used in 2018, 4G in 2009, 3G in 2001, 2G in 1991, and 1G in 1981. The “G” stands for Generation—5G is the fifth-generation cellular standard.

These new standards offer a variety of improvements, but they improve the fundamentals, too: Newer standards are generally faster and provide a stronger signal. That’s how we went from slowly browsing the web on the original iPhone (or a BlackBerry) to streaming high-resolution videos on modern smartphones.

New cellular standards take some time to become widespread and appear in the products they use. Not every phone sold since 2018 is a 5G phone, for example: The iPhone gained 5G support for the first time in 2020.

Modern Networks Don’t Support Old Standards

While cellular standards are changing quickly, that’s not exactly the reason why old phones can’t connect to modern networks. The precise reason is that cellular carriers drop support for old standards to free up resources for new standards.

For example, as of early 2021 in the U.S., the big carriers all support 5G, 4G, and (for now) 3G. They no longer support 2G or 1G.

Let’s say that you have a first-generation iPhone, also known as an iPhone 2G. It’s a classic! But you can’t use it on a modern cellular network today: It only supports 2G. (If you’re an Android fan, take pride in the fact that the first Android phone, the HTC Dream/T-Mobile G1, started out with support for 3G.)

The iPhone only gained support for 3G with its second-generation model, which was called the iPhone 3G. That iPhone 3G can still connect to modern networks—for now, at least, until they drop support for 3G.

Why Networks Drop Support for Old Standards

Maintaining support for older cellular standards is a trade-off. As AT&T argued in a press release when it shut down 2G at the beginning of 2017, phasing out 2G freed up more wireless spectrum that could be used for newer standards—in particular, making the 4G network faster.

Like Wi-Fi, cellular connections are just radio waves. And also like with Wi-Fi, cellular providers only have a specific range of radio frequencies that they can use for their networks. If they use a “band” of that spectrum to keep 2G going, they can’t use that same band for 4G. If they shut down their 2G network, they can reallocate that band (portion of the wireless spectrum) to newer, faster networks that more devices are using.

After all, people upgrade their devices frequently. When the vast majority of people are using modern devices that support the latest standards and only a few people are using older devices, there’s very little reason to keep those old networks running. It may be cheaper for a cellular network to offer discounted device upgrades—or even to give away free devices that support modern standards—to the few customers who are holdouts, rather than to spend resources keeping an old network running.

This doesn’t mean that you can’t keep using feature phones—but you have to buy a modern feature phone with support for modern cellular standards. (Yes, they do exist!)

3G Is Going Away in 2022 or 2023 (in the US)

As of early 2021, there are some big 3G shutdowns coming in the next few years. Cellular carriers in the U.S. say that they will shut down their legacy 3G networks in 2022 or 2023. Only devices that support 4G or 5G will then be able to connect.

The exact details are still up in the air. Verizon said that it would shut down its 3G network at the end of 2020, but in early 2021, the company reportedly set a new target of 2023. AT&T says that it’s shutting down 3G in 2022. T-Mobile plans to phase out its 3G networks through late 2021 and early 2022.

When that happens, your old iPhone 3G, iPhone 3GS, iPhone 4, or iPhone 4S won’t connect to a cellular network anymore. (Android phones from before the 4G era will be cut off, too.)

But the iPhone 5 will still connect. It was the first iPhone to support 4G, and it was released in 2012. (Android phones with 4G support will still connect, too. The first Android phone with 4G was the HTC Evo, released in 2010.)

A Decade Is a Long Time, but Not by Historical Standards

Realistically, most phones released in the past decade will still be able to connect when these networks are shut down. That’s still a pretty generous period of time.

But it’s pretty short compared to historical precedents: By 2022, we imagine you’ll still be able to connect that touch-tone phone from the 1960s to your landline.

Credit to: How To Geek - Chris Hoffman