HLR phone data is essential to mobile telephony; it allows a network to know where its users are, and how to find them. However, the way that this information is shared across the industry is a security risk and doesn’t play well with GDPR compliance. For example, revealing that someone has been roaming can reveal the location of their home and their belongings to burglars, as well as potentially exposing whether they are at home or away.

Many businesses use HLR phone data to identify inactive numbers, reducing their SMS messaging costs and increasing the effectiveness of their marketing campaigns. A bulk HLR lookup can also identify fake numbers used for SIM swap fraud, virtual disposable numbers or otherwise unreachable mobiles, allowing companies to quickly remove these from their contact lists and concentrate on their most active prospects.

HLR Lookup Explained: Understanding the Role of Home Location Register in Mobile Communications

An HLR lookup is a more advanced form of phone number validation, querying a carrier’s HLR database directly to check the status of a phone number. This real-time carrier lookup identifies whether a number is active, disconnected or invalid. It can also provide the MSIDN, subscriber name, line status and other metrics. The result of an HLR lookup can be very useful to a wide range of applications including SMS aggregators and other processing companies, who may be required to comply with GDPR.

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