Enter your . The default code for O2 is usually 0000 . Method 2: Using Network Dial Codes
Navigate to → Supplementary services (or "Calling accounts" on some devices). Select Call barring and choose Voice calls .
For most monthly subscribers, the easiest way to manage bars is through the My O2 portal. Log in to your . Navigate to "Device" or "Manage My SIM." o2 call barring
It is critical to note that O2, like all carriers, requires a (often defaulting to 0000 or 1234, or a four-digit code provided upon account setup). Users who forget this password cannot deactivate bars through their phone’s interface and must contact O2 support, which can be frustrating in urgent situations.
O2 provides multiple pathways to manage these bars. The most universal method is through the phone’s native dialer using MMI (Man-Machine Interface) codes. For example, dialing **21*[password]# and pressing send might bar all incoming calls, while ##21# removes the bar. However, the most user-friendly method is via the O2 mobile app or online account portal, where toggles and checkboxes allow for intuitive management. Enter your
There are several types of call barring that can be used on an O2 mobile phone:
O2 Call Barring stands as a mature, reliable, and often underutilized feature of the GSM ecosystem. It transforms the mobile phone from a passive receiver of all incoming requests into an actively managed communication tool. Whether deployed by a cost-conscious parent, a roaming executive, or a security-minded individual, network-level barring offers a level of control that software-based solutions cannot match. However, its effectiveness hinges on user education—understanding the difference between network bars and phone settings, remembering the service password, and acknowledging its limitations with data and emergency services. In a world of endless interruptions, O2 Call Barring provides not just a barrier, but a choice. Select Call barring and choose Voice calls
This is usually the easiest way to manage specific call types (like international or roaming calls) without memorizing codes.