Caller identification is a system that allows people to see the phone number of the person calling them. These systems can be used to help screen out unwanted calls or provide a record of numbers that attempted to call while the owner was away from the phone. There are several ways to look up caller ID, depending on local regulations and the phone service provider. To see the caller's information without picking up the phone, the customer usually will need to subscribe to an extra service from his phone company. Some customers also have access to caller return services, which will allow users to recover the number of the last incoming call.
The most common method that people use to look up caller ID is to add a service to their existing phone service that will allow users to see the number of an incoming call. While many modern telephone models support this service, some users may need to install a caller ID display to see the incoming numbers. Most caller ID displays will store multiple numbers, so subscribers can use this service as a log of calls made to them while they were away. The ID system may display a name and number or just a number. Cell phone subscribers often have caller ID service included as part of their contract.
Another popular method used to look up caller ID is known as caller return service. This service allows customers to use a special code — *69 in many markets in the United States — to receive the number of the last call made to their phone. Unlike regular caller ID services, this system only provides a number, not the name of the last caller. Most phone companies charge a small usage fee for this service. The customer can then call this number back or try to use a reverse number directory to find out more information about the caller.
While both of these services can be used effectively to look up caller ID, neither is guaranteed to provide results. Individual callers can use call blocking services to keep their information from appearing on a caller ID display and from being accessed using caller return. The use of calling cards or pay phones also can limit the effectiveness of caller ID systems. Telemarketing companies can use several methods to get around caller ID, including blocking or spoofing their number information.