Cellphone caller IDs may be restricted for different reasons such as a telemarketing company or a collection agency that uses a subscription service to mask its caller information. Callers may also dial a code before making a phone call to mask their caller ID, which then shows as restricted.
Restricted IDs are often used by companies in an attempt to avoid a non-answer because of call screening by the recipient. The calling line identification restriction is a function of caller ID and may be used on a call-by-call basis. An override function for this service exists, and authorities such as the police can access the caller information.