HLR lookup

An HLR lookup is a query associated with the Home Location Register, a database used in mobile networks to maintain subscriber information. In commercial telecom usage, the phrase often describes a number intelligence check that returns information such as a mobile network or an indication of reachability. The precise fields depend on the provider, network access and destination country.

A lookup is not a telephone conversation and does not establish that a person will answer. Number portability, roaming, cached records and network restrictions can affect how a result should be interpreted. A negative or unknown response needs context rather than an automatic assumption that the number is invalid. Teams should document the source and time of each check, use the minimum information necessary and distinguish network information from customer consent. A technically reachable number is not permission to contact its subscriber.