How to Fix: Outbound calls blocked or labeled as spam or scam likely

November 30, 2022

Table of Contents

  • What is a Nuisance Call Label?
  • How do I remove a nuisance label from my Twilio phone number?
  • Will registering my number resolve mislabeled calls?
  • Should I register numbers I just purchased?

What is a nuisance call label?

Customers who conduct legitimate voice business may notice that their outbound calls are getting marked with nuisance call labels, such as ‘Scam Likely’, ‘Spam’, ‘Fraud Risk’, ‘Robo Call’ or some variant based on an app, device or network. This can be frustrating, and could result in outbound calls going unanswered or even getting blocked. 

How do I remove a nuisance label from my Twilio phone number?

Here are a few steps you can take to address Nuisance labels on your phone number.

  • US Numbers: Register your US numbers with the FCC. The FCC established this free registry site,, which covers the main analytic companies that support major US wireless carriers that can remove a negative label on a call.
  • International Numbers: At this time Twilio is not able to assist with removing nuisance  labels from international numbers. Please reach out to the terminating carrier that is marking your calls as spam and work with them to register your number or correct the nuisance label.
  • Updating CNAM on your phone numbers may increase the likelihood of answered calls by providing accurate caller information. THIS FEATURE IS IN BETA – release date is TBD.
    • CNAM stands for Caller ID Name. CNAM is a feature in the United States public telephone network that identifies an incoming caller by a personal or business name associated with the originating phone number. You can also choose to remove any CNAM currently assigned to a number. This is helpful when you purchase a new number as CNAMs are not automatically removed when users release ownership of a number.
    • CNAM will not remove a Nuisance label, but may increase answer rates due to the proper display of caller information applied to the call.

Will registering my number resolve mislabeled calls?

While number registration often resolves mislabeling, it is not a whitelist or a guarantee of avoiding mislabeled calls in the future. Registered numbers can still be flagged again if certain call patterns are detected, inconsistent with registered usage or if consumers submit spam or fraud reports against the number. 

Therefore, we recommend the following key practices:

Should I register numbers I just purchased?

Yes, nuisance labels are not automatically removed from a number when the previous owner releases them. It is a best practice to register any newly purchased numbers.

How do I know if this is what I need to do?

In support we hear it described this way, “…when I click to call I am not able to connect to the client. I hear a message like: ‘the number provided was invalid’. Then I called from my personal phone and I was able to connect with the client”.

In this case, the carrier for your client’s phone has decided that the system number is a spam caller, and they have blocked your call by playing a message, ‘…number invalid’. It is time to register your system phone number as instructed above.