BT statement on mobile calling issues
Tuesday 29 July - 14:00
Closing update:
Our services continue to work as normal following the technical fault impacting voice calls last week. We are confident that we have resolved this issue and have now seen network stability across both weekend and weekday traffic peaks.
We apologise for any inconvenience caused.
Further information:
- The root cause was a software issue affecting mobile calls - specifically the ‘Interconnect Border Control Functions’ (IBCF).
- The IBCF connects voice calls to and from phone numbers hosted by other mobile network operators.
- While we now understand the root cause of the issue and the fix remains stable, we continue to conduct enhanced monitoring across our networks as a precautionary measure.
Saturday 26 July - 14:10
Latest update: Following a further fix overnight to a technical fault impacting voice calls on our network, we’ve been monitoring the situation throughout the day and services have been running as normal. We continue to conduct enhanced monitoring to prevent recurrence. We sincerely apologise for any inconvenience this issue has caused.
Friday 25 July - 19:45
Following yesterday's technical fault, we are currently experiencing similar mobile calling issues today. The impact appears to be less widespread but we are working to resolve this as quickly as possible and sincerely apologise for any inconvenience caused.
Further information:
- We’re working to assess the impact for customers.
- Only traditional mobile voice calls are affected.
- Calls to 999 and data calling (like WhatsApp) are working as normal.
- We are working hard to fully restore service for customers.
