Securing Roaming
- Roaming expands reach but opens new doors. The ability for drivers to charge across networks depends on trust between operators, but weak controls can let unauthorised sessions slip through.
- The cost adds up fast. Fraudulent roaming sessions not only erase revenue, sometimes in six-digit sums annually, but also complicate billing, increase settlement disputes, and erode trust between partners.
- Secure roaming is a shared responsibility. Operators must adopt common safeguards, validate roaming traffic continuously, and act quickly on anomalies to keep cross-network charging safe and reliable.
Roaming has been one of the great enablers of Europe’s electric mobility rollout. It allows drivers to plug in anywhere, regardless of who operates the charger, creating the seamless experience customers expect. Behind the scenes, however, roaming depends on a chain of trust between multiple operators and intermediaries. When that trust is not reinforced with proper safeguards, it can be abused.
The risk is best illustrated by the problem of unauthorised sessions via roaming. In this scenario, a fraudulent request travels through the roaming network and is accepted as if it came from a legitimate partner. The result: a driver appears to charge without ever being billed, or a session is recorded against the wrong operator.
The consequences are significant:
Revenue leakage: Operators lose income for each unauthorised session. In several cases, losses have reached six-digit sums annually, unnoticed until settlement cycles revealed the gap.
- Operational overhead: Billing mismatches require manual reconciliation, delaying payments and straining partner relationships.
- Reputational damage: Drivers who see errors or inconsistencies in their charging history lose confidence in the service.
- Strategic risk: If trust in roaming weakens, the entire value proposition of cross-network charging suffers.
Recent real-world cases have shown how attackers exploit gaps in contract validation, identity checks, or session reporting. In some instances, entire blocks of fraudulent sessions were injected into the system, leaving operators with disputes that took months to resolve.
Addressing this risk requires operators to think beyond interoperability as a technical feature and start treating it as a security-critical function. Key actions include:
- Strengthening validation – every roaming request should be checked against clear rules, rejecting those that don’t match expected patterns.
- Continuous monitoring – operators need visibility on anomalies such as unusually long sessions, unexpected roaming partners, or sudden spikes in usage from a single ID.
- Clear escalation paths – when anomalies occur, there must be an immediate alert, a traceable source, and a defined workflow to contain the risk.
- Data sharing and collaboration – fraud attempts rarely stop at one operator. By sharing anonymised alerts, the sector can cut off attacks faster and reduce repeat incidents.
Roaming is indispensable for driver convenience and for the wider energy transition. But just as physical access and unsecured connections can be exploited, so too can the trust links that underpin roaming. Operators, platforms, and partners must therefore treat roaming security as a priority, not an afterthought.
By adopting stronger validation, real-time oversight, and collective reporting, the industry can preserve the promise of roaming while protecting revenue and customer confidence. Unauthorised sessions don’t just cost money. They undermine the credibility of Europe’s EV charging ecosystem. Protecting roaming means protecting the future of e-mobility itself.