What blocking your cell number means and how it works

Blocking your cell number prevents the person you call from seeing your phone number on their caller ID. Instead, they see "Unknown," "Private," or "Blocked" on their screen. This is different from blocking incoming calls — you are controlling what information you send out, not what comes in.

Your carrier (AT&T, Verizon, T-Mobile, or another provider) handles this on their network. When you block your number, the carrier strips it from the call signal before it reaches the other person's phone. The call still goes through normally; the recipient just cannot see who is calling.

You can block your number for a single call, for all calls you make, or for specific contacts. The method depends on your phone type and which option you choose.

Key Takeaways

  • You can block your number on individual calls by dialing *67 before the phone number on most carriers, or by using your phone's settings to hide your number for all outgoing calls.
  • iPhone users can toggle "Show My Caller ID" off in Settings > Phone, while Android users find this option under Settings > Call Settings or Similar, depending on the phone model and carrier.
  • Blocking your number does not prevent the call from going through — the recipient simply cannot see your number, though some people may not answer calls from unknown numbers.
  • Emergency calls (911) always transmit your number to dispatchers regardless of your blocking settings, as required by law.
  • Some businesses and government offices may refuse to work with you if you call from a blocked number, so check their policies before blocking.

Block your number on a single call using *67

The fastest way to hide your number on one call is to use the *67 code. This works on most carriers and most phone types, though some carriers or phone plans may not support it.

Here is the step-by-step process:

  1. Open your phone's dialer (the app you use to make calls).
  2. Type *67 before the phone number you want to call.
  3. Dial the full number as usual (for example: *67-555-123-4567).
  4. Press the call button.

The recipient will see "Unknown" or "Private" instead of your number. This blocks your number only for that single call. Your next call will show your number normally unless you use *67 again.

If *67 does not work, your carrier may not support it, or your phone plan may have restrictions. Contact your carrier's customer service to ask whether this feature is available on your account.

Block your number for all calls on iPhone

If you want to hide your number on every call you make, you can turn off caller ID on iPhone. This setting applies to all outgoing calls until you turn it back on.

Follow these steps:

  1. Open the Settings app on your iPhone.
  2. Scroll down and tap Phone.
  3. Tap Show My Caller ID.
  4. Toggle the switch to off (it will turn gray).

Now when you call anyone, they will see "Unknown" or "Private" instead of your number. To show your number again, return to this same menu and toggle the switch back on.

This setting overrides the *67 code — if you have turned off "Show My Caller ID" in Settings, your number will be blocked on all calls, even if you do not use *67.

Block your number for all calls on Android

Android phones store this setting in different places depending on the manufacturer and carrier. The most common location is in the Phone app settings, but Samsung, Google Pixel, and other brands may organize it differently.

Try this first:

  1. Open the Phone app (the dialer you use to make calls).
  2. Tap the three-dot menu icon (or settings icon) in the top right corner.
  3. Tap Settings.
  4. Look for an option called Caller ID, Show My Number, or Hide Number.
  5. Select the option to hide or block your number.

If you cannot find this menu, the setting may be in a different location on your phone. Try opening Settings > Apps > Phone > Permissions, or contact your carrier. Some carriers manage this setting through their own app instead of the phone's built-in dialer.

Once you have found the setting, toggling it off will hide your number on all outgoing calls. Toggle it back on to show your number again.

What to know before blocking your number

Blocking your number has real consequences in some situations. Many businesses, banks, and government offices will not answer calls from blocked numbers, or they will ask you to unblock before they can help you. If you are calling a doctor's office, your insurance company, or a government agency, check their policy first or be prepared to unblock your number when they ask.

Some people simply do not answer calls from unknown numbers. If you are calling someone who does not know you well, they may let it go to voicemail. Leaving a voicemail with your name and callback number can help, but there is no may provide they will call back.

Emergency calls to 911 always transmit your number to the dispatcher, regardless of your blocking settings. This is a legal requirement so emergency responders can locate you if the call is disconnected.

If you block your number and then call the same person repeatedly, they may report the calls as harassment. Blocking your number does not make repeated unwanted calls legal or acceptable.

Troubleshooting: *67 is not working

If you dial *67 and the call still shows your number, or if the call does not go through at all, a few things could be wrong. First, make sure you are dialing *67 before the phone number, not after. The code must come first: *67-555-123-4567, not 555-123-4567-*67.

Second, check whether your carrier supports *67. Some carriers, especially prepaid or regional carriers, do not offer this feature. Call your carrier's customer service line and ask whether caller ID blocking is available on your account. If it is not, you can use the phone settings method instead (the iPhone or Android steps above).

Third, if you have turned off "Show My Caller ID" in your phone's settings, *67 may not work because your number is already blocked on all calls. In this case, turn the setting back on and try *67 again.

If none of these steps work, contact your carrier directly. They can confirm whether the feature is active on your account and troubleshoot from their end.

Frequently Asked Questions

Will the person I call know I blocked my number?

They will see that the call came from a blocked or unknown number, but they will not receive a notification that you specifically blocked it. Some people may assume you are calling from a business or that the call is spam, so they might not answer.

Can I block my number for text messages?

No. Text messages do not use the same caller ID system as phone calls. Your number will always appear on text messages you send. If you want to send anonymous texts, you would need to use a third-party app or service, which is outside the scope of your phone's built-in features.

If I block my number, can the person trace who called them?

Not through normal means. Your number is hidden from their caller ID. However, if they report the call to law enforcement or their carrier, those organizations may be able to trace it through the phone network. Blocking your number does not make you anonymous to carriers or authorities.

Does blocking my number cost extra?

No. Using *67 or turning off caller ID in your phone settings is included with your phone plan at no additional cost. Your carrier does not charge a fee for this feature.

What happens if I block my number and then call 911?

Your number will transmit to the 911 dispatcher automatically, even if you have blocking turned on. This is required by law so emergency responders can reach you if needed. The blocking setting does not apply to emergency calls.