When 2G first launched in 1991, it marked a leap into a new era of digital mobile communication. Since then, the network infrastructure has evolved quickly. From the first commercial launch of 3G in the UK in 2003 to devices like the iconic iPhone 3G introduced in 2007.
Now, as 4G and 5G networks take over, O2 has announced it will be switching off its 3G network by 31st December 2025, with 2G usage being restricted from 1st January 2026.
For anyone using an older mobile device or SIM, you’ll find yourself in hot water (and without mobile service). We’re helping our business mobiles customers check if their device or SIM is 4G/5G compatible, and how to switch to the right solution. Read on for a quick guide on the 2G/3G switch off.
So, why the move away from 2G and 3G? The goal is to repurpose the older 3G spectrum to boost the quality and speed of 4G/5G networks. The move will offer faster connections, better coverage and more reliable mobile performance UK wide.
Any mobile phones that rely on 2G or 3G for calls or data will need to be upgraded to a device or SIM card as soon as possible to avoid being without a connection. Check if you fall into one of these categories:
This change might feel a bit overwhelming, but the good news is it’s easy to check if your current setup is future-proof or not.
If you’re an RHM customer and you’re not sure if your phone fits into these criteria, our specialists can tell you. Chat to our experts to find out.
You can also use O2’s device checker to see whether your device or SIM is compatible.
If you’re running an older SIM card, it may not support newer networks. If your SIM is more than 5 years old or you’re unsure, contact the RHM Helpdesk and we can support you with any upgrades.
Our team’s top tip: Look at the SIM card itself. If it says ‘3G’ or lacks the ‘4G’ logo, it will likely need replacing!
If you’re running any 2G or 3G-only devices, these will stop working for calls and data by the end of 2025, so it’s important to check what your tech is compatible with, especially if you have multiple mobile phones across your business.
If you’ve received a text or email from us, it means your device needs upgrading and won’t work after December 2025. If you haven’t received a text but you’re wanting to get peace of mind or discuss an upgrade, we can support you with the best options and tariffs. Call the RHM Helpdesk on 03453377373 to ask for a quote for a replacement phone that is 4G compatible.
Our team’s top tip: If you’re already due an upgrade, now is the perfect time to future-proof your business mobiles setup. Check out our business mobiles packages and services.
Modern mobile services like VoLTE (Voice over LTE) and Wi-Fi calling offer users high-quality voice services over 4G.
We enable these features by default on new connections, but we’re also rolling out a project to enable VoLTE and Wi-Fi calling on older connections where possible.
If you’ve noticed poor call quality, or if your device doesn’t have VoLTE, reach out to us to review your setup.
2G won’t be switched off entirely just yet, but it will be limited, only supporting these essential services:
As we move towards a 4G/5G future, businesses need to be prepared. Let’s make sure you stay connected well beyond 2025. To make sure your team is running compatible business mobiles technology, get in touch to review your plan and avoid unnecessary charges.
Get on top of your business mobiles solution to avoid disruption to your business.
If you’re an RHM customer and unsure about your mobile setup, head to our website, call us on 0345 33 77 373 or email: orders@rhmtelecom.com.
© rhm telecommunications 2025
