Various exemplary embodiments relate to a subscriber profile repository (SPR) for determining a subscriber associated with a set of subscription identifiers. The subscriber profile repository may include: an interface which receives a subscriber profile request including at least one subscription identifier; a subscriber record database that includes a set of subscription identifiers; a subscriber record cache that contains a subset of the records contained in the subscriber record database; and a search manager that queries the subscriber record cache using each subscription identifier and queries the subscriber record database when the subscriber record cache does not contain a record matching a subscription identifier. The SPR may also include a results manager that compares subscriber records and updates the cache when a result is found in the subscriber records database. Various exemplary embodiments relate to a method performed by the SPR and a machine-readable medium including instructions for an SPR.