Caller ID is a widely used phone system feature that identifies an incoming caller by name and phone number. The feature isn't perfect, and it can sometimes misrepresent a caller's identity. But for the most part, caller ID is a valuable piece of information. It's offered by just about every commercial phone provider, including landline, VoIP, and mobile phone services.
However, unlike local number portability (LNP), caller ID is not regulated by a governing body such as the Federal Communications Commission (FCC). Rather, the service is essentially a patched-together network of decentralized databases that frequently operate with outdated information.
If your business does not have caller ID set up, it's a good idea to talk to your phone company. Oftentimes, it's one of the first pieces of information you present to a potential customer, partner, or affiliate. Inaccurate or missing caller ID information can preclude people from answering your calls. You're missing out even if you lose just one customer due to something so simple.
To help you navigate some common issues related to caller ID, we put together some of the most frequently asked questions and answers on the subject.
What Is Caller ID?
Caller ID provides the name and number of a calling party, if available. Technically, Caller ID only supplies the phone number of the calling party, but the term has become synonymous with the caller name ID. The name of the calling party is actually provided by a caller name delivery service known as CNAM.
How Does Caller ID Work?
When a call is made, the originating phone switch sends the caller's number. Then, with the caller's number, the callee's service provider is responsible for looking up the caller's subscriber name.
When Caller ID was developed, the world was primarily a realm of Plain Old Telephone Service (POTS) lines, and the caller information came through the Central Office switch to which the wires were connected. Since there were relatively few carriers at the time, it was easy to find Caller ID information and relay it.
Today, with the prevalence of wireless and VoIP phones, hundreds of local/long distance carriers, consolidations, mergers, and the like, the map has become much more fragmented. Unlike phone numbers and domain name service (DNS), where there are internationally recognized databases that are authoritative sources, there is no central authority or regulation for Caller ID.
While there aren’t any FCC guidelines to regulate carrier accuracy, there are federal regulations, like the Truth in Caller ID Act of 2009, that make it illegal to use false Caller ID information with an intent to defraud or scam a called party. However, carriers can maintain their Caller ID databases as they see fit.
How Is the Call ID Phone Number Determined?
The phone number displayed by caller ID is determined by the calling party. For a landline, the displayed number corresponds to the phone number that's registered to the line. For a PRI or SIP connection, the phone system can actually control what number gets displayed on a case-by-case basis.
Note: You may have seen the term “phone ID.” This refers to a phone’s IMEI (International Mobile Equipment Identity) or MEID (Mobile Equipment Identifier). These are unique numbers that are assigned to each piece of phone hardware, like an individual iPhone, rather than a phone number you use to call someone.
How Is the Caller Name Determined?
The Caller ID name is retrieved by the receiving carrier. The receiving carrier queries a CNAM database to determine the name registered to the provided phone number.
What Is a CNAM?
CNAM (“Calling NAMe”) is an outside telecom service that phone companies use to pair incoming numbers with names. Unlike phone numbers, CNAMs are not centralized databases. A carrier can choose from many different CNAMs. Each CNAM maintains its own private database on phone number/name pairs in the United States and abroad.
How Many Characters Does a Call ID Display?
A caller ID outputs up to 15 ASCII characters to display a name, and a typical display name is 9 to 12 characters. The phone number is usually displayed as a ten-digit number.
How Do I Change My Business Caller ID Name and Number?
It's possible to request changes to your caller ID phone number and name, with varying layers of customization, depending on your phone service provider. Some providers require you to call a customer service representative to make a request. Other providers allow you to change caller ID data directly from an online interface.
Landline Phone Numbers
The caller information for Plain Old Telephone Service (POTS) lines is tied to the physical wires connected to the phone company's central switch. For this reason, analog lines will always display the number that's associated with the line itself.
You can change the display name for an analog line by requesting a name change for the number associated with that line. This process will likely involve calling your carrier’s customer support line and requesting a manual change.
VoIP Phone Numbers
Unlike landline services, VoIP services allow you to modify the caller ID display number in addition to the name. Some providers even allow you to configure this information directly via a web interface, without needing to contact a support representative.
Hosted VoIP companies typically send caller ID name updates to the central CNAM databases within 24 hours. As far as phone numbers go, VoIP lines do not have the same wire/number pairing as analog lines do. A VoIP service can usually pass any phone number of your choosing to the person you're calling.
However, this number will still get cross-referenced with the caller's CNAM service, so the CNAM name associated with that number will be displayed. VoIP services do pass a name identifier with caller ID info, but most carriers do not display that data unless it's a SIP to SIP (extension to extension) call.
Most landline services apply the same name and phone number across users, but some VoIP providers allow you to apply unique caller ID name/numbers to individual users within the phone system. This feature is helpful for security, caller authentication, and customization purposes.
Why Isn’t My Caller ID Info Updating?
Ultimately, it comes down to how quickly the new data is relayed to a CNAM and how fast the other carriers pick up on the change. Getting the data to the CNAM can take anywhere from a few minutes to a few days; getting it to the other CNAMs can take much longer.
If you call someone and their phone carrier uses the same CNAM as your provider, then your Caller ID info should update almost immediately. However, updates from different CNAMs could take up to several weeks.
The best you can do is to make sure that your phone company has updated your information to its CNAM and then wait for the changes to circulate. Unfortunately, there is currently no expedited option.
Can Caller Information Be Faked?
With Internet calling technology, caller ID is prone to camouflage and spoofing. The most important thing to remember is that caller ID is not a feature that confirms a caller's identity. It's really an estimate designed to give you context as to who is trying to contact you.
Caller ID remains a staple of every type of phone service, and for good reason. Saved contacts have become the norm and people are inundated with phone calls. They’re simply less likely to pick up the phone if they don’t recognize who is calling. That’s why you should do your best to make sure your business is represented properly with its Caller ID information.
While it may take time for your new information to properly display on all of your outbound calls, the process is still a valuable investment to make sure your business is presented in the best way possible. Make those characters and digits count.
How Does OnSIP Call Identification Work?
We offer caller ID for our OnSIP customers, and we don't charge extra for it. We offer this feature by querying a reputable CNAM database.
On an inbound call, the call is often sent from the Public Switched Telephone Network (PSTN), with a ten-digit number transmitted by the caller's provider. We take that number and look it up in the CNAM database we use, and if it’s associated with a name, we send it to the OnSIP callee's registered phone(s) for display. Usually, the name is between 9 and 12 characters. If there is no information on file, we send a best approximation of the geographic area for the phone number (e.g., New York, NY).
Outbound caller ID works the same way: We send the number to the PSTN, and the callee's provider does the lookup against its database, which may not be the same as ours.
If the callee's provider uses the same CNAM database as we do, chances are the Caller ID name you have set in your account or user record will accurately appear there. We send all updates made by OnSIP subscribers to our CNAM provider every night, and the changes can show up quickly—in as little as 24 hours. So if an OnSIP customer updates her Caller ID settings, the change will be quickly evident if she calls someone whose telephone service provider uses the same CNAM database. However, the information may take a while, sometimes weeks, to be passed on to other CNAM databases.
When a call is made to a cell phone, most times the phone does a lookup against the contacts in the phone’s address book, and if the number isn’t there, will display “unknown.” This varies across providers, so check the service level of the individual provider for exact information.