What is HLR?

General Information

The HLR (home location register) is a database mobile network operators maintain which contains each customer's international mobile subscriber identity (IMSI).

An IMSI uniquely identifies each customer of the mobile network and allows different network operators to send messages and calls to subscribers on other mobile networks.

Each subscriber's SIM card contains their IMSI which does not change. Because a network operator always references the IMSI of the SIM card then the customer of the network can then change their mobile number without changing their SIM card.

In European GSM networks the HLR also stores (and sometimes shares) the wireless customer's entire user profile.

This profile includes calling restrictions, fee charge rates, call forwarding details, additional billing components and in conjunction with a Visitor Location Register (VLR) the subscriber's current location in the network.

When a telecommunications carrier wishes to send a message or call to a mobile recipient the SMSC of the carrier will send a query to interrogate a home location register (HLR) over the SS7 network.

The HLR will respond with the appropriate routing information on how to pass the message or call to the intended subscriber.

HLR Lookup Overview

HLR Lookup provides an internet facing gateway to allow fast, affordable access to the HLR Lookup subsystem.

Ported number detection, roaming location, subscriber status and number validation can be accessed using a centralised interface.

HLR Lookup members do not need signalling equipment, interconnect agreements, telecoms infrastructure or a carrier license to perform HLR checks.

HLR Lookups can be performed via our bulk upload facility or through our secure API.

Registering an account is free.

Files can be uploaded in a number of formats and we have a dedicated team in place to provide any support where needed.