Receive robocalls or text message spam?
Help shut the spammer down.

Most reputable telecom carriers don't want unsolicited messages on their network or phone numbers. In order to disconnect their abusive customers, they need to hear about the abuse. That's where you come in.

Here's how to report abuse to the telecom carrier that is responsible for the spammer's phone number – so the carrier can terminate their service. As one carrier wrote back, "Please be advised that the offending traffic has been removed from our network." For more background, see FAQ.

How to report abuse

1. Identify the spammer's real phone number
2. Find the telecom carrier responsible for that number
3. Report abuse to the responsible carrier

1. Identify the spammer's real phone number

If you received a phone call (robocall, voicemail)

Ignore the phone number that the call appears to come from (Caller ID). With phone calls, that number is usually forged ("spoofed"). Instead, report the phone number that the call instructs you to contact.

If you received a text message (SMS, iMessage)

Report the phone number that the text message appears to come from. With SMS and iMessage, the sending phone number is generally correct. It is difficult to forge. If the message instructs you to respond by texting or calling a second number, consider also reporting the second number.

2. Find the telecom carrier responsible for that number

Look up the carrier on one of these free sites:

• realphonevalidation.com
• freecarrierlookup.com

Alternatively, look up the carrier using a carrier lookup API operated by Twilio or Plivo. These APIs provide more accurate responses, allow more lookups, and have command-line tools. See How do I look up more numbers?

3. Report abuse to the responsible carrier

The Web site or API response will provide the name of a telecom carrier, such as "Bandwidth," "Peerless," or "Telnyx." That is the carrier to contact about this number (see Carrier contacts).

Here are example responses for 5 different phone numbers:

"Bandwidth"
"Bandwidth/Zipwhip - Toll-Free - SVR"
"T-Mobile USA, Inc."
"Telnyx - Telnyx - SVR"
"Twilio - Toll-Free - SMS-Sybase365/MMS-SVR"

When the carrier name mentions multiple companies, as in some of the examples above, contact the first company named. For example, if the carrier name is "Twilio - Toll-Free - SMS-Sybase365/MMS-SVR," contact Twilio. If the carrier name is "Bandwidth/Zipwhip - Toll-Free - SVR," contact Bandwidth.com.

Be professional and respectful. The carrier you are contacting is the carrier which routes calls and texts to this phone number. They may not have been the carrier through which the unsolicited text or robocall originated. However, they can disconnect service to the phone number. Reputable carriers disconnect customers for generating unsolicited ("opt-out") bulk calls or texts.

In addition, report the message to your wireless provider so that they may try to block texts or calls to their other subscribers. See Reporting abuse to your wireless provider.

Carrier contacts

Also see Reporting abuse to your wireless provider.

What to include

• The phone number that you want them to investigate
• How you were contacted (phone call or text)
• Day and time when you were contacted
• Your phone number

Optional but recommended:

• A clear statement that you did not provide permission for this organization to contact you
• (If readily available) The text of the message or transcription of the voicemail

When the carrier responds, make sure that they don't simply remove your phone number from the abuser's list – while ignoring the other victims and the abuse. The carrier should investigate the end customer for unacceptable use or ask their downstream customer to do so. If needed, ask the carrier to ask their customer to provide proof that you opted in.

Frequently Asked Questions

How does this help?

Most US-based carriers don't want phone spam to use their network or phone numbers. In order to disconnect abusive customers, they need to hear about the abuse. Here's a real reply from a carrier: "Please be advised that the offending traffic has been removed from our network."

How is this different than…

How is this different than using the "Report Junk" (iOS) or "Block & report spam" (Android) buttons, or a call reporting app provided by your wireless provider?

Those reports are sent to your own wireless provider and/or the phone OS manufacturer (Apple or Google). It helps them try to block/filter similar messages, so that other subscribers are not bothered. However, those reports don't reach the carrier that is providing service to the organization that's annoying you. This page explains how to report abuse to the carrier that can actually shut off the spammer's phone numbers.

Also, the instructions on this page work for phone calls, while "Report" buttons or blocking the number mostly don't help with phone calls.

How is this different than blocking the number?

Blocking a phone number is a bit better than nothing, but not much. With phone calls, the originating phone number is usually spoofed, so blocking has almost no effect. With text messages, the originating phone number is generally not spoofed, but senders constantly rotate through outbound numbers.

What about political or non-profit organizations?

Most reputable telecom carriers don't allow unsolicited mass messages, regardless of content. Report it.

How do I look up more numbers, obtain more accurate data, or use an API?

Create a free account with Twilio or Plivo. Then, use the Twilio or Plivo number lookup APIs to discover which carrier the abusive number(s) are routed to.

Twilio

To use Twilio Line Type Intelligence API, run:

curl -X GET \
  'https://lookups.twilio.com/v2/PhoneNumbers/+14151112222?Fields=line_type_intelligence' \
  -u 'YOUR-TWILIO-ACCOUNT-SID:YOUR-TWILIO-AUTH-TOKEN'

Replace 4151112222 with the phone number you want to find the carrier for. The line_type_intelligence hash contains a carrier_name field with the carrier name (example). Your Twilio API tokens can be found here.

Plivo

To use Plivo Lookup API, run:

curl -X GET \
 `https://lookup.plivo.com/v1/Number/+14151112222?type=carrier` \
  -u YOUR-PLIVO-AUTH-ID:YOUR-PLIVO-AUTH-TOKEN

Replace 4151112222 with the phone number you want to find the carrier for. The carrier hash contains a name key with the carrier name (example). Your Plivo API tokens can be found here.

Sometimes I get text messages from email addresses, not phone numbers. What are they?

These could be Apple iMessages. See What is the difference between iMessage and SMS?. Apple manages all iMessage access. For unsolicited iMessages, push "Report Junk" to send the message to Apple.

These could also be text messages which were relayed through your wireless provider's text-to-email gateway. Some wireless providers let outsiders send email that the wireless provider forwards to you via text message. Very few people use text-to-email gateways; if you don't, consider contacting your wireless provider to disable email-to-text functionality on your account. Learn more: AT&T, T-Mobile, Verizon.

Other

Reporting abuse to your wireless provider

This site is about reporting abuse to the carrier responsible for the sending phone number(s). In addition, you can and should report spam to your own wireless provider. Your reports help your wireless provider block unsolicited calls and messages from reaching other subscribers.

In short:

• For unsolicited calls: Strongly consider installing the call filtering and call reporting app that your wireless provider provides: AT&T ActiveArmor, T-Mobile Scam Shield, Verizon Call Filter. Report unsolicited calls using that app.
• For text message spam: Use the "Report Junk" button (iOS) or "Block & report spam" (Android) button. If the message does not show a report button, copy and paste the text message to 7726 (SPAM). See FTC: How To Report Spam Text Messages.
• Add your number(s) to the National Do Not Call Registry.

Not in the US or Canada?

This site focuses on abuse from US/Canada phone numbers, called the "North American Numbering Plan." The process described above is likely work for telecom abuse from numbers in other countries, though different carrier lookup services may be needed. However, the lookup services mentioned in this page may work; for example, Twilio states "Worldwide support" for their carrier lookup API. Try them and see.

Help tech-savvy friends

Help tech-savvy friends discover that they can do something meaningful about phone spam. Draft a post on:

• Facebook
• LinkedIn
• Mastodon
• Twitter

… or compose an email to a friend.