Effective date: 1 October 2025 (with temporary extended access for selected operators)
Applies to: All international roaming SIMs using O2 UK (including Conexa, excluding O2 Global/Telefonica Spain)
What’s changing?
From 1 October 2025, O2 UK began withdrawing inbound roaming on its 2G and 3G networks.
However, O2 has since confirmed that temporary extended access was granted to a small number of roaming partners to give IoT deployments using legacy modules limited additional time to upgrade.
This means some devices may still be connecting to O2 2G/3G in certain areas, even after the original switch-off date.
This temporary access:
is only available to selected operators
is not guaranteed
may be removed at short notice
does not reverse the shutdown
does not apply to all SIMs within those operators
Customers should not rely on this temporary access and should continue migrating devices away from O2 2G/3G. Wireless Logic will notify customers as soon as O2 or any roaming partner confirms withdrawal dates for this temporary access.
O2 is continuing its strategic transition toward 4G, 5G, and LPWAN, which are more efficient and future-ready technologies.
KPN SIMs
KPN is the only operator that has issued a confirmed phased shutdown schedule.
Please see our dedicated article: KPN SIMs – O2 UK 2G/3G Inbound Roaming Switch-Off
3G roaming
No longer available anywhere in the UK (O2 was the last UK operator supporting 3G).
2G roaming
Still available on EE and Vodafone, depending on your SIM’s roaming profile.
Temporary 2G access on O2 may still occur for some SIMs due to extended access granted to selected roaming partners, but this should be treated as temporary and not relied upon for service continuity.
What this means for your devices
2G/3G-only devices will not be able to roam on O2 UK once temporary access ends.
4G/5G-capable devices will continue to work, but may need the correct configuration.
When inbound 2G/3G roaming is withdrawn for your operator, devices should automatically connect to the next available roaming partner.
No SIM refresh is required
If your device loses service, restarting (power cycle) can help reconnect more quickly
Voice services
Voice calls will continue on 2G where available (depending on your SIM profile).
If supported, alternative voice calling like 4G Calling (VoLTE) can also be used for voice.
Once O2 completes its 3G shutdown, 3G voice will no longer be available in the UK.
Device settings – LTE module behaviour
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Some LTE modules operate in two different modes, which can affect connectivity once 2G/3G are no longer available:
Voice-centric mode: Devices expect a 2G/3G voice path. Without it, they may struggle to register or connect in a 4G-only environment. This has caused issues during 2G/3G shutdowns in other countries.
Data-centric mode: Devices use LTE data only and continue to work smoothly in a 4G-only environment.
To avoid issues, we recommend configuring devices in data-centric mode wherever possible.
Steering devices away from O2
Some devices may still attempt to connect to O2’s 2G network during the temporary access period. To reduce service disruption, you may need to adjust network-selection behaviour. Many IoT modules allow network priorities or blocks to be set at hardware or firmware level.
Why steering matters
As O2 continues its 2G withdrawal, any inbound 2G registration attempt may be rejected. O2 will return a cause code marking the O2 network as forbidden in the SIM memory:
The forbidden entry remains for 24 hours or until the next power cycle
Devices will not attempt O2 again during this period
Devices can still connect to Vodafone or EE 2G, where supported by your roaming profile
Steering devices away from O2 ensures they connect directly to available alternatives rather than repeatedly attempting O2.
Multi-operator SIMs
If your SIM can connect to multiple UK operators:
It will continue based on each operator’s own 2G/3G shutdown timeline
After O2’s withdrawal takes effect for your operator, O2 2G/3G inbound roaming will no longer be available
After 3G sunsets are complete UK-wide, no UK network will provide 3G roaming
Fallback networks may still offer 2G, depending on your SIM’s roaming profile
Wireless Logic will notify customers of any confirmed changes to operator shutdown timelines.
What you should do
To avoid service disruption and prepare for the future, we recommend:
Upgrade devices to 4G, 5G, or LPWAN-compatible hardware.
Enable VoLTE (4G Calling) for voice-capable devices.
Set LTE modules to data-centric mode for reliable connectivity.
Review roaming profiles to confirm fallback networks such as Vodafone or EE 2G.
Consider adjusting device network-selection settings to steer devices away from O2, as temporary access may be withdrawn without notice.
Need help?
If you have questions about device upgrades or need guidance on suitable alternatives, please contact your Wireless Logic account manager or email us at sales@wirelesslogic.com. Our team is here to help you plan and ensure a smooth transition.
For general queries or technical support, you can also reach our support team at support@wirelesslogic.com.
For more information on network sunsets worldwide, see our page on Global 2G & 3G network closures.