Mobile operators worldwide are switching off their 2G and 3G networks to free up spectrum for 4G and 5G. In the UK, the major networks have announced their shutdown timelines, with most 3G services ending by 2025 and 2G following in the years after. For businesses that rely on SMS — particularly those with IoT devices, M2M systems, and embedded hardware — this raises an important question: what happens to your text messages when these networks go dark?
The answer is reassuring. SMS is not just surviving the network transition — it is emerging stronger than ever.
The UK shutdown timeline
Each UK mobile operator is managing its network transition on its own schedule:
- Vodafone: 3G switched off in 2024. 2G to remain operational until at least 2033 to support IoT and M2M devices
- EE (BT): 3G shutdown completed in 2024. 2G to continue for legacy device support
- Three: 3G shutdown in progress (2024-2025). Three never operated a 2G network
- VMO2: 3G shutdown planned for 2025. 2G retained for IoT and emergency services
The pattern is clear: 3G is being retired first, while 2G is being retained longer specifically because of its importance for M2M communication — much of which relies on SMS.
Why 2G matters for SMS and IoT
Millions of devices worldwide are built on 2G modules that use SMS for communication. These are not smartphones — they are embedded systems in industries including:
- Fleet management — vehicle tracking units that report location and status via SMS
- Smart meters — energy and utility meters that send readings via 2G SMS
- Security systems — alarms and monitoring devices that send SMS alerts
- Vending machines — cashless payment terminals using 2G for transaction processing
- Agricultural sensors — remote monitoring equipment in areas with limited network coverage
- Medical devices — health monitoring systems that alert via SMS when thresholds are breached
These devices were designed for longevity — many have 10-15 year operational lifespans. Replacing them all at once is impractical and costly, which is why operators are keeping 2G alive longer than 3G.
SMS on 4G and 5G: stronger, not weaker
There is a common misconception that SMS is tied to older network technologies. In reality, SMS works across all generations of mobile networks — 2G, 3G, 4G, and 5G. The protocol has been adapted for each generation:
- 2G/3G: SMS transmitted via the circuit-switched signalling channel
- 4G (LTE): SMS delivered via SGs interface or SMS over IMS (IP Multimedia Subsystem)
- 5G: SMS fully supported via the 5G core network architecture
On 4G and 5G networks, SMS actually benefits from improved infrastructure — faster delivery, better reliability, and enhanced security. The transition to newer networks does not degrade SMS; it enhances it.
What businesses need to do
If your business uses SMS for customer communication — marketing campaigns, appointment reminders, notifications, or authentication — the network transitions have no impact on your messaging. SMS sent via a provider like Faretext is delivered through the SMS API to the mobile operator, which handles the network-layer delivery regardless of whether the recipient is on 4G or 5G.
However, if your business operates IoT or M2M devices that rely on embedded 2G modules, you should:
- Audit your device estate — identify which devices use 2G-only modules and which support 4G
- Check your operator's timeline — confirm when your network operator plans to switch off 2G in your area
- Plan hardware migration — for 2G-only devices, plan a phased upgrade to 4G-capable modules. Many modern IoT modules support LTE Cat-M1 and NB-IoT, which are designed specifically for low-power, low-bandwidth M2M communication
- Consider multi-network SIMs — roaming SIMs that can connect to any available network provide resilience during the transition period
LTE-M and NB-IoT: the future of M2M messaging
The successors to 2G for IoT are already deployed across UK networks. LTE Cat-M1 (LTE-M) and Narrowband IoT (NB-IoT) are 4G technologies specifically designed for the use cases that 2G currently serves:
- Low power consumption — battery life measured in years, not months
- Low bandwidth — perfect for small data payloads like SMS, sensor readings, and status updates
- Wide coverage — designed to penetrate buildings and reach remote locations, matching or exceeding 2G coverage
- SMS support — both LTE-M and NB-IoT support SMS natively, ensuring continuity for M2M messaging
For businesses planning their IoT migration, these technologies provide a clear upgrade path that preserves SMS capability while delivering improved performance and longer device battery life.
The global picture
The UK is not alone in sunsetting legacy networks. The GSMA reports that over 130 mobile operators worldwide have announced or completed 2G and 3G shutdowns. Key markets include:
- United States: AT&T shut down 3G in 2022; T-Mobile completed 2G/3G shutdown in 2024
- Australia: Telstra shut down 3G in October 2024, with Optus and TPG following
- Japan: NTT Docomo shut down 3G in March 2026
- Germany: Vodafone Germany shut down 3G in 2021; 2G retained for IoT
In every market, SMS has continued to function seamlessly through the transition. The protocol's network-agnostic nature is one of its greatest strengths — and a key reason why businesses sending international SMS can rely on delivery regardless of the recipient's network generation.
Why SMS remains the safest bet
While app-based messaging platforms require smartphones, data connections, and specific software, SMS works on every mobile device on every network generation. As 2G and 3G are retired:
- SMS continues on 4G and 5G — fully supported with improved delivery infrastructure
- No app required — recipients do not need to update, download, or install anything
- Universal reach preserved — the transition does not reduce SMS reach; it simply moves delivery to newer, faster networks
- Regulatory reliance — SMS remains the mandated channel for emergency alerts, banking notifications, and government communications in most countries
For businesses evaluating their communication strategy, SMS is the one channel that has demonstrated resilience through every generation of mobile technology — from the first text message in 1992 to the 5G era and beyond.
Faretext delivers your messages via direct Tier 1 carrier connections that automatically route through the optimal network path. Whether your recipient is on 4G or 5G, our SMS API ensures reliable delivery. Get started with 25 free credits.
Frequently asked questions
Will the 2G/3G shutdown stop my SMS messages from being delivered?
No. SMS is supported on all network generations including 4G and 5G. Messages sent via Faretext are delivered through carrier infrastructure that automatically handles routing regardless of the recipient's network type.
When will 2G be switched off in the UK?
Most UK operators plan to retain 2G until at least 2030-2033 to support IoT devices and legacy systems. 3G is being retired first, with most shutdowns completing in 2024-2025.
Do I need to upgrade my IoT devices that use SMS?
If your devices use 2G-only modules, you should plan a phased migration to 4G-capable modules (LTE-M or NB-IoT) before your operator's 2G shutdown. Both technologies support SMS natively.
Is SMS more reliable on 4G/5G than on 2G?
Yes. SMS on 4G and 5G benefits from improved network infrastructure, faster delivery times, and enhanced security compared to legacy 2G delivery. The transition actually improves SMS performance.
Will RCS replace SMS when 2G/3G is switched off?
RCS enhances the messaging experience on compatible devices but does not replace SMS. When RCS cannot be delivered, it falls back to SMS. The two protocols coexist, with SMS remaining the universal fallback for guaranteed delivery.
