Issue

What steps should I take if my Twilio number is being impersonated or spoofed, and how can this issue be effectively resolved?

Product

Twilio Programmable Voice and Messaging

Cause

Twilio does not support or allow SMS or voice phone number spoofing. If you have confirmed that your Twilio account credentials are secure and there is no unauthorized activity in your logs, it is likely that the spoofing is occurring outside of Twilio’s services. This is unfortunately a common issue in the telecom industry, and Twilio cannot prevent third parties from spoofing your number on other networks.

Resolution

• Contact Your Local Carrier: Report the spoofing to your carrier. They may be able to trace or block the offending traffic.
• Report to Regulatory Authorities: Consider reporting the incident to relevant authorities (such as the FCC in the US).
• Inform Callers: If you are receiving angry calls, you may wish to update your voicemail to let callers know your number is being spoofed and you did not make the calls. Scammers typically move on to new numbers quickly.

• Monitor Your Account: Continue to monitor your Twilio account for any unusual activity. If you suspect fraud, please contact our Fraud team at fraud@twilio.com

   

Additional Information 

Best practices to prevent spoofing:

• Secure your PBX and SIP infrastructure (strong passwords, firewalls, HTTPS).
• Keep all software and integrations up to date.
• Protect authentication tokens and never expose them publicly.
• Run anti-malware software on all devices accessing Twilio.
• Monitor your account regularly for unusual activity.

Learn more: 

1. Does Twilio support SMS phone number spoofing?

2. Why Am I Getting Angry Calls from People Who Say They Received a Call from my Twilio Phone Number?
Explains caller ID spoofing, what it is, and what you can do.

3. Protect your Twilio Account Against Phone Number Fraud

4. Technical documentation on anti-fraud practices for phone numbers and messaging

5. How to use proxy numbers to protect your real phone number

6. Best practices for validating and verifying phone numbers to reduce fraud