Why is my 5G so slow? Comparing the hype to the reality

5G is often presented as a monolithic technology, a single vehicle to carry all mobile data needs. In reality, it's anything but. Not only do the three major carriers in the US all offer their own flavors of 5G services, there are also multiple wireless frequencies being used to transmit those services across each network. 

Our guide to C-Band 5G, which we'll touch on more later, has a detailed look at exactly how those frequencies are used by each carrier. But the important thing to address here is the fact that there is relatively little in the way of obstacles to stopping a carrier from slapping a 5G logo on top of its smartphone screens, even if it might not deserve to. 

In fact, AT&T tried to be the first out of the gate in the US to offer "5G" services by rebranding what was essentially its unaltered, existing 4G LTE services as "5G E." As you might expect, the confusing, questionable advertising decision did not go over well. In fact, AT&T wound up having to backpedal from the whole fiasco and pay a monetary settlement after Sprint (now owned by T-Mobile) filed a false advertising lawsuit against it. 

So, why are some 5G connections so slow? The first, and most impactful, reason is that the far-reaching 5G signals that have powered the vast majority of carrier rollouts in the US – especially from AT&T and, to a lesser extent, T-Mobile – have used low-band carrier frequencies. These frequencies (850MHz for AT&T and 600MHz for T-Mobile's early efforts) can reach miles from their towers. The downside is that their speed capacities are generally below 100Mbps in real-world conditions, right in line with what could already be accomplished with a solid 4G LTE connection. 

Another important factor is widespread use of a technology called Dynamic Signal Sharing (DSS). This protocol allows carriers, including AT&T and Verizon, to use the same spectrum bands for both 4G LTE coverage and 5G coverage. The benefit is that some existing equipment and spectrum bands can expedite 5G rollouts by eliminating the need for new construction and spectrum license acquisitions. 

Unfortunately, while the 5G side of DSS is legitimate 5G, of a sort, its actual performance is, in Verizon's own words, "comparable to [its] award-winning 4G LTE." This is due to a combination of factors, including congestion, the limitations of older hardware, and the same reliance on low-band frequencies. 

Simply put, the most widespread types of 5G currently available in the US all fall under the category of 5G services that are no faster than 4G, and offer relatively little in the way of comparative benefits aside from being widely available.

Not only does it exist, but we're finally entering a period where a large portion of the country, not just the lucky few in densely populated urban centers, will benefit from it. 

Until recently, the only 5G rollouts that have truly exceeded the speed and capacity 4G could already provide have been those that relied on either mid-band or high-band frequencies. 

T-Mobile did particularly well in the early 5G race thanks – and still does, in large part – to its decision to purchase Sprint. That acquisition brought with it access to the spectrum licenses and nascent tower network Sprint had been working on, both of which used the 2.5GHz band. This is a mid-band frequency, a segment of coverage that is considered a sweet spot for 5G services that combines impressive speeds with enough range and penetration to offer coverage areas that can still be measured in square miles. 

Verizon and AT&T, on the other hand, had been relying almost exclusively on high-band deployments until their recent C-Band debuts. Verizon's fastest 5G had always relied on the 28GHz and 39 GHz millimeter wavelength spectrum bands. These higher frequencies provided download speeds that could easily exceed 1Gbps, or more than 10 times what its DSS-based network could provide. The downside is that those speeds were only available, in Verizon's own estimation, within a range of just "1,500 feet without obstructions."

T-Mobile

If you're a T-Mobile customer, you've probably already seen improvements since the company essentially completed its nationwide rollout of 5G in late 2021. Its 2.5GHz service offers a nationwide average of about 150Mbps, according to Opensignal, with speeds that can easily reach 400Mbps or more in densely covered areas. Both of those measurements should continue to climb as the carrier continues to "densify" its network with new hardware and infrastructure. 

Verizon

For Verizon Wireless subscribers, the wait is either over, or will be soon. The company's C-Band launches operate between 3.7GHz and 3.98GHz, putting them in the same sweet spot as T-Mobile's. 

Early tests from our sister site CNET have shown speeds as high as 1.4Gbps under ideal conditions, with 400Mbps being available over a wider area, and 90Mbps being possible even when deep within an underground garage. 

Verizon's claims its initial rollout (which was forced to skip US airports over interference concerns) includes a total of 46 "major metro areas." Each rollout also measures in square miles, unlike previous high-band launches that would be lucky to reach a full city block. The company expects to continue expanding its markets in the coming year. 

AT&T

AT&T subscribers might have the longest to wait of all the "Big Three" carriers. Its initial rollout saw C-Band go live in a much smaller number of cities, eight specifically. However, like Verizon it has big ambitions for the future, claiming its new spectrum of 5G services will reach 200 million people by the end of 2023. Unfortunately, it hasn't provided any details on where these potential customers might be located. However, thanks to a recent agreement being reached between AT&T, Verizon, and the Federal Aviation Administration, US airports may soon get access to the new technology as it continues being carefully rolled out around air travel hubs in a manner that won't impact US commercial flights.