The simplest way to block your number on a single call
On most phones in the United States, you can block your number for one call by dialing *67 before the phone number you're calling. Type *67, then the full number including area code, then press call. The person who answers will see "Private Number," "Blocked," or no number at all on their caller ID.
This works on landlines and most mobile phones. On iPhone, Android, and other smartphones, the process is identical — just dial *67 first. The block applies only to that single call. Your next call will show your number again unless you dial *67 again.
If *67 doesn't work, your phone carrier may use a different code. Some carriers use #31# instead. Try *67 first; if it fails, contact your carrier to ask what code they support.
Key Takeaways
- Dial *67 before the phone number to block your number on a single call in the United States.
- The recipient will see "Private Number" or "Blocked" instead of your phone number on their caller ID.
- The block lasts only for that one call; your number will show on the next call unless you dial *67 again.
- Some carriers use #31# instead of *67, so try that code if *67 does not work on your phone.
- Blocking your number does not prevent the call from going through, but some businesses and government offices may not accept calls from blocked numbers.
When blocking your number may not work
Some phone numbers will not accept calls from blocked numbers. Banks, government offices, hospitals, and customer service lines often reject private calls automatically. If you call a blocked number and the call drops or you hear a message asking you to unblock your number, that business does not accept private calls.
In those cases, you have two choices: call without blocking your number, or contact the business through a different method like email, their website, or visiting in person. There is no way to force a business to accept a blocked call.
Blocking your number permanently on all calls
If you want your number blocked on every call you make, not just one at a time, you can set this in your phone's settings or through your carrier.
On iPhone: Open Settings, tap Phone, then tap Show My Caller ID. Toggle it off. Your number will now be blocked on all outgoing calls. To turn it back on, toggle it on again in the same location.
On Android: The process varies by phone model and carrier. Open the Phone app, tap the menu (three dots or lines), go to Settings, then look for "Caller ID" or "Show My Number." Toggle it off. If you cannot find this setting, contact your carrier — some carriers control this through their own app instead of the phone's settings.
On a landline: Call your phone company and ask them to enable "Caller ID Blocking" or "Anonymous Call Rejection" on your account. They can usually do this over the phone in a few minutes.
What the person receiving your call will see
When you block your number, the person answering will see one of these on their caller ID: "Private Number," "Blocked," "Unknown," "Restricted," or simply no number at all. Different phones and carriers display it differently, but the result is the same — they will not see your actual phone number.
The person can still answer the call and talk to you normally. Blocking your number does not change how the call works; it only hides your number from their caller ID display.
Why you might want to block your number
People block their numbers for different reasons. You might not want a business to have your personal number, or you might be calling someone you do not know well and prefer privacy on that first contact. Some people block their number when calling a business they have had problems with, to avoid being recognized and having the call rejected before they can explain their issue.
Blocking your number is legal in the United States. However, if you are calling a business or government office, they may have policies against accepting blocked calls, and they can refuse to help you until you unblock your number.
The difference between blocking your number and blocking calls from others
Blocking your number (what this article covers) means hiding your number when you call someone else. Blocking calls from others is the opposite — it means preventing specific people from calling you. These are two separate features on your phone.
To block incoming calls from a specific number on iPhone, open the Phone app, find the number in your recent calls, tap the info icon, and select "Block this Caller." On Android, open the Phone app, find the number, tap and hold it, then select "Block number" or "Add to reject list." The exact steps vary by phone model.
Frequently Asked Questions
Will the person know I blocked my number?
They will see that your number is blocked, but they will not know it is you specifically unless you tell them. If they do not recognize your voice, they may not know who called. If you block your number regularly when calling the same person, they may eventually figure out it is you.
Can I block my number on a text message?
No. Text messages do not have a blocking feature like phone calls do. Your number will always appear on any text you send. If you want to send a message without revealing your number, you would need to use a different service like email or an anonymous messaging app.
What if I dial *67 and nothing happens?
Your carrier may not support *67, or you may have a setting turned on that prevents blocking. Try #31# instead. If neither code works, contact your phone carrier and ask if they support caller ID blocking and what code to use. Some carriers charge a small monthly fee for this feature.
Can I block my number on a conference call or video call?
No. *67 only works on standard phone calls. Video calls through apps like Zoom, Google Meet, or FaceTime use your account information instead of your phone number, so *67 does not apply. Your name or account will show instead.
If I block my number, can the person call me back?
No. When you block your number, they have no number to call back. If they want to reach you, you would need to call them again or contact them through another method.