San Francisco CNN Business  — 

5G, the next generation of ultra-fast wireless, continues to expand in the US. The catch, of course, is you’ll need to be in the right city with the right device to access it.

The technology has been touted as a major breakthrough that will allow for better video streaming and more technical advancements, such as connecting self-driving cars.

CNN tech editor Samantha Kelly, who tested the service in several markets, called the current state of 5G in the US inconsistent. On some networks, she accessed lightning-fast speeds, downloading two hour movies in seconds, but often struggled to connect indoors and when blocked by environmental factors, such as nearby trees.

The US has made some solid ground catching up to China’s existing 5G presence. In fact, a report published by the Cellular Telecommunications Industry Association (CTIA) in April, which represents the US wireless communications industry, found the US and China are now tied for first place in 5G readiness.

But analysts don’t expect to see widespread adoption in the US until around 2020.

Here’s where you can get it now from Verizon and AT&T. T-Mobile and Sprint, which are set to merge, also have plans for 5G networks, but the bulk of those plans likely won’t roll out until 2020.

Verizon

In May, Samsung’s Galaxy S10 5G – the first smartphone in the US that could access the network without an attachment – launched on Verizon’s network in the mobile carrier’s first 5G markets: Chicago and Minneapolis.

Verizon has since rolled out service to select parts of Atlanta, Denver, Detroit, Indianapolis, Phoenix, Providence, Rhode Island, St. Paul, Minnesota, and Washington, DC. While still limited, Verizon’s mobile 5G network is expected to expand to over 30 cities by the end of the year.

More devices work on Verizon’s network now, too, including the Galaxy Note 10+ 5G and the LG V50 ThinQ 5G. It also supports other 5G-compatible devices: a 5G MiFi hotspot and the moto z3 and moto z4, which can access the network with the help of a special attachment that resembles a small battery pack.

Meanwhile, Verizon’s 5G home internet service, which works like broadband internet, is already available in select parts of Houston, Indianapolis, Los Angeles and Sacramento, California with a 5G router. More cities are expected to get access to the home internet service in 2019.

AT&T

AT&T (T), which owns CNN’s parent company WarnerMedia, launched its 5G network in several cities in late 2018.

Although some mobile carriers have opened 5G networks to the general public, AT&T’s 5G network is only available for select business and developer customers for now. Those users will need to use either a Galaxy S10 5G smartphone or a Netgear Nighthawk 5G Mobile Hotspot to access it. (AT&T is expected to get the Samsung Galaxy Note10+ 5G by the end of 2019.)

These 21 cities have access to the 5G network: Atlanta; Austin, Texas; Charlotte, N.C.; Dallas; Houston; Indianapolis; Jacksonville, Fla.; Las Vegas; Los Angeles; Louisville, Ky.; Nashville, Tenn.; New Orleans; New York City; Oklahoma City; Orlando, Fla.; Raleigh, N.C.; San Antonio; San Diego; San Francisco; San Jose, Calif.; and Waco, Texas.

Sprint and T-Mobile

Sprint (S) and T-Mobile (TMUS) are moving forward with their plans to merge. Under the terms, both companies will need to stay on track rolling out their 5G networks to keep promises made to regulators or else face fines.

The new T-Mobile that results from the merger with Sprint will have six years from the close to complete its 5G build-out requirements. Dish Network (DISH) will take over Sprint’s prepaid wireless business, including Boost Mobile and Virgin Mobile. Under the deal, Dish will need to build a 5G wireless network capable of serving 70%of the US population by June 2023.

In the meantime, Sprint has launched its network in select parts of Atlanta, Chicago, Dallas-Fort Worth, Houston and Kansas City and plans to expand to Los Angeles, New York City, Phoenix and Washington, DC in the coming weeks. It offer customers four ways to access its 5G network: the Samsung Galaxy S10 5G and the LG V50 ThinQ, the HTC 5G hotspot device and the upcoming OnePlus device.

T-Mobile currently offers access to its 5G network to Samsung Galaxy S10 5G users in select areas of Atlanta, Cleveland, Dallas, Las Vegas, Los Angeles and New York.