CNAM: FAQs about Caller ID Names

In this article we provide answers to frequently asked questions about CNAM. 


How do I update CNAM? 

With Telzio, it’s easy to update caller ID info right through your dashboard. Follow these steps to update CNAM for your business phone numbers. 

  1. Log into your Telzio account. 
  2. Navigate to Plans & Numbers. 
  3. Click on the phone number you want to update. 
  4. Click Update CNAM. 
  5. Enter up to 15 characters as your caller ID name. 
  6. Click Change Caller ID. 

Once you press Change Caller ID, Telzio instantly starts updating the databases. There are several databases that we update to ensure that all the different carriers are displaying the same info for your phone number. 

Again, keep in mind that even after you update CNAM, some providers may store their own information about your number for several weeks, so it can take time before everyone starts seeing your updated caller ID name.

Because it takes time to update all the databases, you can only update CNAM every 2 weeks, so make sure to double check the info you entered. 

Learn more about Business Caller ID from Telzio.


What is CNAM? 

CNAM, or caller ID name, is the name that is displayed when you call someone. You can register your CNAM with your phone service provider so that your name appears in the caller ID along with your phone number. 


How does caller ID work? 

When you make an outbound call to another phone number, it’s up to the receiving carrier to pull your caller ID name and display it on the phone of the person you’re calling. 

Most phone companies in the world today send calls over what’s called an SS7 network. This system is a set of standard protocols that enables different carriers to communicate with each other to connect phone calls and deliver text messages. 

When a call is made, information about the caller’s phone number is transmitted via this network. In order to also transmit the caller’s name, the receiving carrier dips into a line information database. 

Related: How to Set up a Vanity Number in 3 Steps


What is the CNAM database? 

In the US, there are a number of central databases where telephone providers register and retrieve caller ID information. When you update your CNAM with your phone company, the phone company registers this information in the databases, where other phone companies can access the same information to display to their subscribers when you call them. 

If your phone number was in use by another person or company before you, there may already be CNAM data deployed to the central databases. In that case, you definitely want to update the info to show your company name instead. 


What is a CNAM lookup? 

Each time you receive a call, your phone company dips into the CNAM database to look up the current caller ID info of the person calling you, also known as a CNAM lookup. Because phone companies incur a cost for each lookup, most charge subscribers a monthly fee to display caller ID names on incoming calls. 

Many carriers store CNAM info for several weeks. This way, they don’t incur a cost for every single call. The downside with this is that even if you update CNAM for your phone number, it may not show up correctly to everyone right away. 

How current your caller ID display info is, ultimately depends on the carrier of the person you’re calling. 


What does CNAM cost? 

At Telzio, we provide caller ID names on incoming calls at no additional cost. Most other VoIP providers charge an additional monthly fee for this feature. 

There is a small one-time registration fee to update CNAM for your phone number. 


Do toll free numbers have caller ID? 

Caller ID has historically only been available for local numbers and not for toll free. That’s because when toll free numbers were first introduced in the 80s, they were only used for inbound calls. But in the modern age of telecom, many companies have started making outbound calls from their toll free numbers. 

SOMOS, the company appointed by the FCC to manage toll free numbers in North America, has announced that they will release the first beta of their Toll Free CNAM service in October of 2019. 

Telzio will be one of the first to offer caller ID on toll free numbers when it becomes available. 

Related: How to Get Toll Free Numbers

Jennifer is part of the content marketing team at Telzio, providing insight and tips on how Telzio can be used to optimize business communications and customer service.