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No Caller ID: How to know who called

Updated 4 days ago
Published Oct 3rd, 2022 7:45AM EDT

Your phone rings, and it’s from an unknown caller with no Caller ID. Receiving a call from an unknown number can be quite frustrating and worrisome. Getting repeated calls from an unknown number could easily be termed harassment.

These “worrisome” calls might not be threatening to you in small doses as they could easily be telemarketers or even prank calls or texts. However, repeated incoming calls from unknown callers could quickly become very uncomfortable.

Are you ready to stop those annoying phone calls and unmask the Caller ID behind the unwanted calls? We cover some of the best methods to reveal unknown numbers.

How to block unwanted calls from callers with no Caller ID

This is the best solution if you would rather not deal with hidden Caller IDs from unknown callers. Most mobile devices have the feature that enables you to bar numbers without a Caller ID.

Also, the good news is that it can be done on both Android and iOS devices. Here’s how easy it is.

Block Unwanted Calls iPhone (iOS 13 or later)

Step 1

Select Settings on your home screen.

Image source: Toby Grey for BGR

Step 2

Scroll to the Phone option and tap on it.

Phone settings in the iPhone app to block calls with no caller id

Step 3

Scroll to Silence Unknown Callers and toggle it on.

Silence call option to block calls with no caller id
Toggle to turn on the "Silence unknown caller" option for calls with no caller id

All calls without a Caller ID will be automatically blocked from your phone. Also, this will keep them blocked unless you change the settings.

Block Unwanted Calls on Android

Step 1

Open your phone dialer.

Image of phone dialer app

Step 2

Tap the three vertical dots on your phone screen’s top/middle right side.

Phone dialer showing three dots

Step 3

Tap on Settings.

Phone dialer showing settings option

Step 4

Select Block numbers.

Call settings

Step 5

Switch on Block unknown callers.

Block settings

Now, all calls from a blocked Caller ID will be barred from entering your phone.

How to unmask no Caller ID or reveal an unknown caller

The *57 Method

The *57 method of showing caller id.

You should use this method immediately after receiving an incoming call from an unknown caller. Typing *57 on your cell phone sends an immediate request for your service provider to trace your previous caller’s number.

If the Caller ID trace is successful, you will receive a confirmation sound or beep. Alternatively, if the Caller ID trace is unsuccessful, you will receive an error beep depending on your mobile company.

The *57 service is the MCIS (Malicious Caller Identification Service). It is a paid service offered by all major network carriers in the US, including T-Mobile, AT&T, and Verizon. The fee for the service is added to your monthly bill.

Use Caller Identification Tools for calls with no Caller ID.

Truecaller home page

You can use anonymous Caller ID service providers to reveal an unknown caller. Some like True Caller screen the incoming Caller ID of unknown callers and identify them. Other caller identification tools allow you to search for unknown numbers and reveal the caller’s identity.

You can also use these identification tools to block unknown callers and prevent them from reaching your number in the first place. In addition, they can help you automatically block an incoming call from a spam caller.

These services are o available as apps on the Apple App store and Google Play store. Install the apps from your app store and also set it up to begin screening the Caller ID of all incoming calls.

How to Use Caller ID Tools

While the steps might vary across different Caller ID tools, here’s the general way to set up these Caller ID tools:

  • Open the website or app of your preferred tool.
Truecaller sign in
  • Sign up with your email or sign in if you already have an account.
Truecaller search bar
  • Paste the unknown phone number into the search bar and wait for results.

If the trace is successful, you will receive the unmasked phone number containing the real identity of your caller.

Contact your phone company

T-Mobile block scam calls webpage

Your wireless carrier or telephone company can help you identify an unknown caller. The Caller ID of all the private numbers that contact you is available to your phone company. You can always reach out to them if you feel threatened or repeatedly harassed by an anonymous call.

There is no option on your call log to view the details of a blocked call. This leaves you with the option of contacting your service provider. The law prevents your carrier from revealing personal information regarding users to you. Although, they will if you can prove you are being harassed or threatened by the caller.

Most companies will provide up-to-date information regarding the caller, including their name, phone number, and address. However, you might need the assistance of relevant law enforcement agencies to make this possible though.

Pro tip

You must note the time and date of the call. This information will come in handy when you request the caller information from your service provider. There are millions of calls made daily using each carrier, so you must have as many details as needed to trace the call.

So when you receive a call from a blocked Caller ID, note down all the important information. This information will help your mobile carrier track the call and retrieve the Caller ID.

Contact local authorities

Filing a report with the police is a quick way to identify your caller. This is the best course of action if you receive repeated calls from blocked numbers that make you feel threatened.

You will need to state everything you know about these calls. Including the voice or voices you hear, the time of the call, your call list, and other important info. These details will help the police work with your network carrier to uncover the person behind the Caller ID.

Security agencies have advanced techniques they can use to track down the person or persons behind blocked numbers. Using techniques like VoIP and also location routing numbers, they identify the owner of the blocked Caller ID.

No Caller ID vs. Unknown Caller ID

There are important distinctions you should know. No Caller ID and Unknown Caller are two different things.

No Caller ID means that the caller intentionally blocked their ID. On the contrary, an unknown caller means the Caller ID was not recognized even though it was provided. I personally think the best way to handle this is turning on the option to block unknown callers on iOS. It sometimes blocks real callers, but it’s a good balance between being inundated with spam calls all day.


What does no Caller ID mean?

If you receive a call without any Caller ID, the caller has deliberately blocked their phone number from showing up.

What does *57 do on a phone?

The vertical service code *57 activates malicious caller identification. This is an upcharge fee subscription service offered by telephone company providers.*57 should be dialed immediately after receiving a call from a number with no caller ID. When you do so, it records the meta-data of the malicious call to aid law enforcement investigations.

Are unknown calls dangerous?

The answer to this question is not exactly straightforward. Some of these calls could be from pranksters, while others are from malicious actors. If you receive these calls sparingly, they could probably be prank callers.
On the other hand, if you feel your phone number is being targeted continuously with blocked Caller ID calls, you should take it seriously. You could avoid the situation altogether by blocking the calls. Alternatively, take any of the steps we have highlighted above to reveal those behind the calls.

How do you call a number with a blocked ID back?

While it isn’t advisable, you can call the number using the Last Call Return code. This is the North American Numbering Plan Administration’s universal vertical service code (VSC). Dial *69 on landlines or #69 on mobile to automatically call the last number that called you back. There’s usually a time limit on when you can call back after receiving such calls. In most cases, you must do so within 30 minutes of receiving the call.

Should I answer calls with no ID?

Answering a call from an unknown number can be a big security risk. If you do not know the person’s identity on the other end, it’s best not to pick. On the other hand, if you have picked up the call and do not recognize the other person’s voice, end the call immediately.
Many kinds of scams can be done over the phone, and it is quite easy to be a victim. Some of these scams require the caller to record your voice or specific uttered phrases. Although some of these calls could be pranks, you should avoid picking them up if you are unsure.

How do you call a number with a blocked ID back?

You cannot call back a number that calls you with a hidden Id back. If you miss a call from such numbers, you must wait till they call you back. Their hidden id prevents you from calling back if you do not have their number.
However, we advise that you refrain from trying to call such numbers back. Someone you know has no reason to hide their id when they call you.

Will my telephone provider reveal an Unknown Caller’s ID to me?

It is against the law for your mobile carrier to reveal information about another user to you. They can only do so if you can prove that you’re in danger or feel threatened. If you are going to request such details from your mobile carrier, you must have enough evidence to back up your claim.
Another important thing you can do is report the case to law enforcement. This would improve your chances of getting the caller’s identity as they would back you up when you make your request.

How to find an unknown caller for free?

You can find an unknown caller for free by simply using a caller identification tool. For instance, you could use Truecaller by signing up on their website or downloading their app. This way, you can search for the identity of any unknown numbers that call your phone.
Alternatively, Caller ID tools have auto-detection features that you can utilize. This would automatically reveal the identity of a caller immediately after their call comes in.

More coverage: Read more about what the latest iPhone event brought us.

Toby Grey - BGR Guides Contributor

Toby Grey contributes as a How To expert for BGR. Typing away like a keyboard super hero, he covers just about anything you can think of. If Toby isn't writing, he's probably reading a book or playing video games.