// Glossary
HLR Lookup
A query to a mobile carrier's Home Location Register that confirms whether a phone number is provisioned and active on a carrier.
Definition
An HLR (Home Location Register) lookup queries the central database mobile carriers use to track subscribers, returning whether a mobile number is active, its serving carrier, and roaming status, without placing a call or sending a text. Porting and line-type data are typically layered on top from carrier records. It's the phone equivalent of email verification: it confirms a number is active on a carrier before you spend on outreach, reducing wasted sends to dead numbers.