What are unknown numbers?
Definition
An unknown number is a call from a number you don't have saved, or one that shows up with no number at all. The caller may be a real person, a business, an automated call or a scammer.
- Category
- Scams
- Also called
- unknown caller, unknown caller ID, no caller ID
- Last updated
"Unknown" covers two situations. In the first, your phone shows a number but it isn't in your contacts. In the second, the screen says something like "Unknown", "No caller ID" or "Private number" because no number was sent.
There are ordinary reasons for both. A doctor's office, a delivery driver or a government agency may call from a line that isn't saved in your phone, and people can switch off their own caller ID. The FCC points out that blocking your own number so it shows as unknown is not spoofing.
Why scammers like it
Scammers can change what shows on your screen. The FCC calls this caller ID spoofing: a caller deliberately alters the displayed number to hide who they are, often to look local or to pass as a company or government agency. Spoofing with intent to defraud or cause harm is prohibited under the Truth in Caller ID Act.
What the FCC says to do
The FCC's advice is simple: don't answer numbers you don't recognise. If you pick up a suspicious call, hang up, and don't press buttons to "stop calls" or answer questions. If it claims to be your bank or a government office, call back using a number you can verify on a statement or the official website, not the number that called you.
Unknown number vs. spam call
An unknown number only says you don't know the caller. A spam call is an unwanted call, and it can show a number you know, because it was spoofed.
How to protect yourself
- 1
Let it go to voicemail
A real caller will leave a message. Scammers rarely do.
- 2
Hang up on suspicious calls
Don't press buttons, give details or confirm who you are, even for a recorded message.
- 3
Verify before you call back
Use the number on your bill, card or the official website, not the one on your screen.
- 4
Use carrier and phone blocking
Ask your provider about call-blocking tools. Register your number at donotcall.gov, though scammers ignore it.
- 5
Report it
File an unwanted-calls complaint at consumercomplaints.fcc.gov or report scams to the FTC at reportfraud.ftc.gov.
- 6
Get your number off listing sites
Many scam calls use numbers pulled from listing sites. Serus finds where your phone number is listed and removes it.
See where your personal data is exposed
Serus finds it on data brokers and people-search sites and removes it.
Frequently asked
Should I answer unknown numbers?
The FCC advises not answering numbers you don't recognise. If it matters, the caller can leave a voicemail.
Can someone find me from calling an unknown number?
Not by you answering alone, but a scam call can confirm to the caller that your number is active. Hanging up without talking gives them nothing.
What does a no caller ID call mean?
The caller's number wasn't sent. That can be a person who hides their number, a business with a blocked line, or a scammer. Treat it like any unknown call.
Sources
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