Roaming fraud is a type of telecommunications fraud that occurs when someone exploits international mobile roaming services to use voice, SMS, or data without paying, often without the phone owner’s or mobile operator’s knowledge. It typically involves using stolen, cloned and takes advantage of delays in how mobile networks detect and share usage or billing information. Because of these delays and the complexity of coordinating across different networks, the fraud can go unnoticed for some time, leading to significant revenue leakage and financial losses for mobile network operators.
As mobile roaming becomes more widespread through travel, IoT, and eSIM adoption, fraudsters are finding new ways to bypass controls. The increasing complexity of global networks, combined with legacy vulnerabilities in signaling and interconnect systems, has made roaming fraud harder to detect and quicker to scale, turning it into a persistent and costly threat for mobile operators worldwide.
Roaming fraud takes advantage of technical gaps and trust-based processes between mobile operators. Here’s how it works:
When a user roams onto a foreign network, their home operator doesn’t get usage details instantly. This delay gives fraudsters time to rack up charges before any red flags are raised.
Protocols like SS7 and Diameter, used to exchange information between networks, can be manipulated. Fraudsters use these to spoof locations, bypass authentication, or hijack roaming access.
Fraudsters insert roaming SIMs into SIM boxes to generate fake traffic or spoof numbers. These calls appear legitimate but are routed through high-cost or fraudulent channels.
Roaming agreements rely on trust. If even one partner lacks proper fraud controls, attackers can exploit that network as a backdoor into more secure systems.
Without real-time monitoring, fraud goes unnoticed until billing systems catch up, often too late to prevent revenue loss.
Combating roaming fraud calls for multi-layered defenses that operate in real time, adapt to evolving fraud patterns, and integrate seamlessly across the network ecosystem.
Legacy fraud systems often analyze events only after they’ve occurred, which delays response and increases financial risk. Modern approaches focus on real-time monitoring and continuously scanning for unusual usage patterns such as unexpected spikes, irregular destinations, or behavior that strays from the norm. These tools, powered by machine learning, can flag early signs of fraud, uncover hidden fraud patterns, and respond instantly to potential risks.
Modern roaming fraud often targets vulnerabilities in signaling protocols such as SS7, Diameter, and HTTP/2 used in 5G. These protocols can be exploited by injecting malicious messages, altering routing information, or bypassing authentication checks, allowing attackers to spoof device locations, reroute calls or texts, and gain unauthorized access to roaming services.
Strengthening signaling network security involves more than just deploying firewalls. It requires end-to-end visibility, protocol filtering, anomaly detection, and real-time blocking of suspicious signaling messages. Proactively securing the signaling layer helps operators prevent fraud before it can take hold while also protecting subscriber data, service integrity, and inter-operator trust.
Dynamic roaming control enables operators to intelligently manage how subscribers connect to partner networks while roaming based on real-time criteria such as network quality, pricing agreements, and potential fraud risk. By prioritizing trusted partners and avoiding high-risk networks, operators can reduce fraud exposure, optimize service quality, and protect margins. When paired with real-time analytics, this approach helps ensure secure, seamless roaming experiences while adapting quickly to emerging threats.
Timely action is critical in preventing roaming fraud. Automated controls allow operators to respond instantly, blocking high-risk numbers, suspending outbound activity, or applying usage caps. These measures limit potential losses and can be tailored to individual risk profiles, ensuring flexibility while investigations are underway.
Fraudsters exploit gaps between operators. A unified defense strategy built on shared intelligence, collaborative tools, and real-time communication closes those gaps. Engaging in industry groups like GSMA’s FASG and leveraging shared data feeds, real-time alerts, and blacklists significantly enhances early detection and coordinated response.
Many roaming subscribers are unaware of common scams such as Wangiri calls, premium SMS fraud, or silent charges. Proactive communication through alerts, travel advisories, or in-app notifications plays a critical role in reducing fraud impact and building long-term trust.
Neural Technologies’ AI-Driven Fraud Management System (FMS) combines advanced analytics, machine learning, and integrated signaling security to proactively detect and mitigate roaming fraud. Built for scale and flexibility, it helps operators respond faster, reduce losses, and maintain customer trust.
Comprehensive Fraud Detection
Real-Time, Scalable Framework
Flexible and Future-Ready
Unified Monitoring and Case Management
Compliance and Data Protection
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