No large cell carriers have announced specific long-term plans for phasing out 4G cellular. However, all of them have commented in various forums that 4G will eventually be retired, as happened to 3G.

Looking at the lifespan of 3G might be a decent barometer for the lifecycle of 4G. The phase-out of 3G happened in 2022, about twenty years after its introduction. Interestingly, the 3G phase-out was delayed by the pandemic and might have otherwise occurred a little earlier. 4G was introduced into networks around 2010, and that might presage retirement of the technology starting around 2030.

When I researched the question online, I ran across numerous predictions that a 4G phase-out in the U.S. will likely start around 2030. All predictions are that 4G and 5G will continue to coexist until a phase-out begins.

One of the factors that favors 5G is that more customers every year are changing to cell phones with 5G capability. You might think that almost everybody upgrades phones, but when 3G finally was ended, there were still millions who didn’t have a 4G capable phone. Cell phones are increasingly expensive, and there is a significant portion of the public who hangs on to a working phone as long as possible.

One of the problems with phasing out 4G is that a lot of hardware and services are hard-wired to use 4G. For example, there are numerous IoT devices and vehicle systems that only look for a 4G connection. Any device you’ve purchased without a 5G capability will become a brick when 4G is finally retired.

One of the biggest issue of retiring 4G is that the lower frequencies used for 4G carry for greater distances in rural markets. If 4G was cancelled today, a lot of rural neighborhoods and households would lose cell coverage to some extent, and some would lose it totally. It’s possible that carriers will repurpose lower frequencies to 5G, but none of them have announced such plans.

The transition to 5G has been successful. My consulting firm has looked at cellular coverage in several markets, and 5G connections have grown to be roughly two to one over 4G connections in the markets we studied. Interestingly, as more customers migrate to 5G, those networks get busier, particularly at peak time. Conversely, speeds on 4G network seem to be climbing over time as the demand decreases.

There was hope that 4G spectrum could be leveraged to last longer by using Dynamic Spectrum Sharing that allows 4G and 5G to share the same spectrum band. However, an article in LightReading last year says the technology has now been abandoned in the U.S. since the technology did not mitigate signal interference between the uses.