What are spam numbers?

Definition

A spam number is a phone number used to make unwanted calls or texts, such as robocalls, telemarketing or scams. Scammers often fake the caller ID, so the number you see may not be the real one.

Full glossary
Category
Scams
Also called
spam caller, spam phone number, scam number
Last updated

A spam number is a number that unwanted calls or texts come from. Some are real numbers used by telemarketers. Many are not: scammers use fake caller ID information to make it look like they're calling from a different place or phone number. That is why one number often doesn't mean much. The same caller can show up under many numbers, or use a number that isn't theirs.

What the FTC says to do

The FTC's advice comes down to a few habits. Hang up on illegal robocalls and don't call back. Don't press a number to be removed from the list, because that can lead to more calls. Use call blocking and labeling, from your phone or your carrier. And report the call at DoNotCall.gov. The FCC takes complaints too.

Do Not Call doesn't stop scammers

Being on the National Do Not Call Registry doesn't stop illegal calls, because scammers ignore it. Blocking and labeling are the main defence, though not every scam call gets flagged since the caller ID can be faked.

Texts

Most mobile carriers let you report spam texts by forwarding them to 7726 (SPAM). Check with your provider.

Why your number gets called

Your phone number sits on data broker and people-search listings next to your name and address. The more places it is listed, the easier it is for callers to find you and to sound like they know you. That can make a scam call far more convincing.

Spam number vs. spoofing

A spam number is the number the call appears to come from. Spoofing is the faking of that number. A scam call often uses both.

How to protect yourself

  1. 1

    Don't answer, don't press buttons, don't call back

    Hang up on illegal robocalls. Calling back or pressing a key marks your number as active.

  2. 2

    Turn on call blocking

    Check your phone's settings for built-in blocking, and ask your carrier about free or paid blocking and labeling services.

  3. 3

    Report the call

    Use DoNotCall.gov, or the FCC's complaint page and choose 'unwanted calls'. Include your number, the number on caller ID, the date and time. If you lost money, report it at ReportFraud.ftc.gov.

  4. 4

    Take your number off listing sites

    Remove your phone number from people-search and data broker listings. Serus finds where your phone number and address are listed and removes them.

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Frequently asked

How do I know if a number is spam?

Look for calls that start with a recording, ask you to press a key, push urgency or ask for money or personal details. Caller ID can be faked, so don't rely on the number alone.

Does blocking a spam number work?

Only partly. Scammers change caller ID often, so a blocked number may not call again while another does. Call blocking from your carrier or phone, which covers many numbers, works better.

Will the Do Not Call Registry stop spam calls?

No, not illegal ones. Scammers don't care about the registry, so you also need blocking and labeling.

Where do I report a spam number?

Report it at DoNotCall.gov, and file with the FCC at fcc.gov/complaints if you like. If you lost money, use ReportFraud.ftc.gov.

Sources

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