EE, one of the UK’s largest mobile service providers, resolved a multi-day outage caused by a technical fault in its voice call infrastructure. The disruption, which began on July 24, 2025, affected emergency services, businesses, and residential customers, with sporadic issues persisting until July 261. Parent company BT conducted overnight maintenance to restore services, but criticism mounted over poor communication and prolonged downtime2.
Impact and Technical Root Cause
The outage stemmed from an unspecified routing fault in BT’s infrastructure, primarily affecting ported phone numbers3. Customers reported failed 999 calls, dropped connections, and intermittent service degradation. Cross-network disruptions also impacted Vodafone users due to interoperability dependencies4. EE’s coverage checker showed inconsistent signal availability during the incident, despite the provider’s typical 99% UK population coverage5.
Response and Mitigation
BT’s engineering team deployed a temporary fix on July 24, but full resolution required additional overnight maintenance on July 26. EE advised customers to use WiFi Calling as a workaround, though this was ineffective for users without compatible devices or stable internet access6. Ofcom initiated an investigation into the incident, citing potential violations of regulatory service continuity requirements7.
Security Implications for Network Operators
The outage highlights systemic risks in legacy telephony infrastructure, particularly for ported numbers and emergency services routing. Network administrators should prioritize:
- Real-time monitoring of SS7/Diameter signaling protocols
- Redundant failover systems for critical voice routing components
- Transparent incident communication protocols
Compensation claims may arise under Ofcom’s General Conditions, which mandate service credits for prolonged outages affecting emergency access8.
Conclusion
The EE/BT outage underscores the fragility of converged voice networks and the cascading effects of technical faults in critical infrastructure. While services have been restored, the incident will likely prompt regulatory scrutiny and internal reviews of BT’s network resilience strategies.
References
- “EE resolves ‘technical fault’ causing voice call disruptions,” BBC News, Jul. 26, 2025. [Online]. Available: https://www.bbc.com/news/articles/cx2q8qw0q0go
- “Thousands lose EE/BT voice services in UK outage,” BBC News, Jul. 24, 2025. [Online]. Available: https://www.bbc.com/news/articles/cnvmvqrnq7go
- “Vodafone, EE, O2 outage timeline,” TechRadar, Jul. 26, 2025. [Online]. Available: https://www.techradar.com/news/live/vodafone-ee-o2-outage-july-2025
- “EE and Vodafone networks down across UK,” Express.co.uk, Jul. 25, 2025. [Online]. Available: https://www.express.co.uk/life-style/science-technology/2086426/ee-vodafone-networks-down-uk
- “EE/BT UK network still down for some following outage,” Data Center Dynamics, Jul. 26, 2025. [Online]. Available: https://www.datacenterdynamics.com/en/news/ee-bt-uk-network-still-down-for-some-following-outage
