What’s the 3G sunset and how will it affect existing IoT deployments?

As cellular networks roll out 5G, they are continuing to shut down older systems. Learn more about how the 3G sunset will impact your IoT deployment.
Mike Brien
February 24, 2022
sunset behind hill with cell towers

The cellular landscape continues to evolve and post will help guild you on the changes so you don't lose connectivity. We cover:

What is the 3G sunset?

As 4G technologies mature and 5G deployments accelerate, mobile network operators are becoming less reliant on 2G and 3G technologies — both for data and, more recently, for voice. This change provides an opportunity to re-allocate radio spectrum from 2/3G to 4/5G.

The phasing out of these legacy (2/3G) technologies is commonly referred to as their sunset.

This transition can create challenges for deployments that depend on older systems. 2G and 3G are still commonly used technologies for many IoT deployments.

There are several sunset options available to network operators. These often involve a gradual migration of capacity from older to newer technologies, with some operators then choosing to switch off legacy radio networks completely. Therefore, it is important to plan for the 2/3G sunset and prepare your IoT deployment for migration to newer cellular technologies.

Recommended reading: 5G vs. 4G: Key similarities and differences

Why is the 3G sunset happening?

With the addition of upgraded networks, like 5G, mobile carriers look to shut down their older services, like 3G. This practice is used to free up spectrum and the infrastructure needed to support new services.

When will the sunset happen?

There’s not a single cutoff date for 2/3G technology. Carriers around the world have different strategies for updating their infrastructure. Some have already retired both 2G and 3G (Verizon, for example, no longer guaranteed 2G and 3G service after the end of 2019), while others are holding onto one or both for the foreseeable future. It’s important to know which carrier network your devices use so you can adequately prepare for the sunset.

Dates to be aware of

Upcoming 3G sunsets in the U.S.:

  • AT&T on 02/2/22
  • Sprint on 03/31/2022
  • T-Mobile on 07/1/22
  • Verizon on 12/31/22

Upcoming 3G sunsets in Canada:

  • Bell on 12/31/2025
  • Telus on 12/31/2025
  • Rogers on 12/31/2025

3G sunsets in Asia:

  • Many carriers in Asia have already enacted a 3G shutdown, including China Mobile, China Unicom, and all carriers in Taiwan.
  • Airtel (India) in March 2020


  • Telstra plans a complete 3G shutdown by 2030
  • Vodafone turned off 2100MHz in 2019 but continues to support 900MHz

Most European carriers have already or will soon phase out 3G:

  • EE by 2022
  • Three and Vodafone in 2020
  • Orange France by 2021
  • Sweden Telenor by 2025

Why some regions are phasing out 3G before 2G

While most Asian and American network operators opt to retire 2G first, Europe’s carriers are retaining 2G while retiring 3G service. They made this decision because 2G was the first choice for numerous IoT applications that are still in use today. Many IoT use cases (smart meters, for example) only need to occasionally transmit small packets of data, so 2G connectivity is sufficient. The cost of replacing these existing devices is also an important consideration.

How will the 3G sunset affect existing IoT deployments?

2/3G capacity will diminish slowly in most places, with freed bandwidth reassigned to 4/5G.

Ultimately the sunset of legacy networks will impact every device not capable of 4/5G, from IoT sensors to tablets and smartphones — regardless of manufacturer. It’s important for IoT managers to inventory their devices to know which ones will be affected.

To maintain consistent coverage, devices that do not support 4G will ultimately have to be upgraded to 4G or one of the IoT-specific cellular solutions.

Prepping your fleet for the 3G sunset

First and foremost, it’s important to know what spectrum your fleet operates on. If you are operating on 3G, and it will be sunsetting, you need to plan to migrate off of the network to avoid losing connectivity. Depending on your use case, lconnectivity could lead to increased risks as it relates to compliance and cost. For remote patient monitoring, this could mean the difference in a patient's health outcome. For fleet management or micromobility, losing track of a device or vehicle in the field can add thousands to the bottom line — and the list goes on.

3G sunset checklist for fleet managers

There’s a lot to keep in mind if you are migrating off of 3G. Here are some steps to consider:

  • Know your fleet: Create a device inventory to know which devices may be at risk of losing connectivity. Leveraging a dashboard (https://www.hologram.io/products/dashboard/) from your provider can also help streamline this process.
  • Know your options: Transitioning off of 3G is a great time to re-evaluate providers and ensure you are setting yourself up for success in the future.
  • Create a plan: Determine what’s needed to complete the migration and create a timeline to complete the transition before the sunset occurs.
  • Swap your SIMs: Schedule the time to swap your SIMs in the field, taking into account installation time. Leveraging a SIM with eUICC capabilities, that can receive over-the-air updates, will help protect your fleet for the future.

Planning for the migration in a way that won’t impact your bottom line will help make the transition a smooth process.

What are the benefits of switching to 4G LTE?

For some IoT use cases, 4G LTE will be the most logical migration destination for your deployment. For many global operators, 4G is now a mature technology offering substantial coverage, and carriers are not planning to sunset this technology in the near future, so it’s also future-proof. Here are a few other advantages of 4G LTE versus 3G:

  • Higher bandwidth 4G LTE data speeds are significantly faster than 3G. If your deployment involves high volumes of data (such as streaming video), this will benefit you.
  • Lower latency 4G LTE offers lower latency than 3G. This can help with deployments that depend on real-time data delivery — for example, connected cameras or other devices used by first responders during emergencies.

If the cost of hardware and power consumption is a priority — and your deployment does not require high bandwidth connectivity — it might be better to explore cellular standards that are specifically designed with IoT in mind.

Recommended reading: How to understand the different LTE IoT device categories

What are the benefits of switching to 4G IoT technologies?

3GPP specifically designed LTE IoT standards to provide solutions for IoT devices; some of the primary aims were to deliver lower device cost, reduce power usage, improve coverage, and support a large number of devices. Therefore, these standards can be excellent options depending on your use case and are highlighted below:

  • LTE Cat-1 This category was introduced in 3GPP Release 8 as an introduction to machine-to-machine (M2M) communication. With DL/UL maximum speeds of 10/5 Mbps Cat-1 is able to handle higher bandwidth needs and supports Voice over LTE. Cat-1 is a viable choice for asset tracking, remote sensors, wearables, and micro-mobility.
  • LTE Cat-M Cat-0 was introduced in 3GPP Release 12, followed by Cat-M1 in Release 13 and Cat-M2 in Release 14. Cat-M was designed to have low device complexity and costs, coverage enhancements, long device battery lifetime, support of a massive number of devices, and deployment flexibility. Cat-0 and Cat-M1 have a maximum DL/UL speed of 1Mbps, and Cat-M2 enhances this by allowing the use of additional bandwidth and other enhancements to achieve maximum DL/UL speeds of 4/7Mbps. Cat-M1 hardware boards are much less expensive than other options and provide excellent coverage—and the technology is compatible with existing cellular data services, making it a future-proof choice.
  • NB-IoT NB-IoT was first standardized in 3GPP Release 13 as a cellular solution to competing Low Power Wide Area Networks. Like LTE Cat-M, NB-IoT had the radio access design principles of low device cost, low power consumption, coverage improvement, massive Machine Type Communication, and deployment flexibility. The small amount of bandwidth available for NB-IoT results in maximum DL/UL speeds of 26/66 Kbps, which might seem low, but is still suitable for many IoT applications.

Recommended reading: Understanding data transmission speeds

Migrating your deployment

The 3G sunset may initially seem intimidating; however, it is also an opportunity to re-envision long-term plans and upgrade deployed devices to the latest technology that’s best for your use case. Additionally, the options highlighted above will likely result in short-term and long-term cost savings.

You can future-proof your deployment with a Hologram SIM card. Our IoT SIM card offers seamless, global coverage for IoT devices with access to LTE/4G/CAT-M technologies as well as 3G and 2G where available. And you can trust your devices will connect and stay connected even as new networks are launched. With our Hyper eUICC-enabled SIMs, you’ll gain access to new connectivity partnerships without any additional carrier negotiations, integrations, or hardware swaps.

Get started with Hologram today

  • Talk to an IoT expert
  • Receive a free SIM
  • Customize your plan