The basic method: use *67 before the number

On most landlines and cell phones in the United States, dialing *67 before a phone number hides your caller ID from the person receiving the call. Type *67, then the full phone number including area code, then press call. The recipient will see "Private Number," "Blocked," or "Unknown Caller" instead of your phone number.

This works on a per-call basis — you do not change any settings on your phone. Each time you want to hide your number, you dial *67 first. If you forget to dial *67, your number shows normally. The next call you make will show your number again unless you dial *67 again.

Some phone carriers and phone systems do not support *67. If you dial it and your number still shows, contact your carrier to ask whether they offer this feature. A few carriers charge a small monthly fee to use it regularly, though most include it at no cost.

Key Takeaways

  • Dialing *67 before a phone number hides your caller ID on most U.S. phone lines, showing the recipient "Private Number" or "Unknown Caller" instead.
  • *67 works on each individual call — you do not need to change phone settings, and your number shows normally on the next call unless you dial *67 again.
  • Some carriers do not support *67, and a few charge a monthly fee, so contact your carrier if it does not work on your phone.
  • The recipient can still see your number if they have a service that unblocks private calls, and some businesses reject all blocked calls automatically.

When *67 does not work or is not available

If you dial *67 and your number still appears on the recipient's phone, your carrier may not support the feature. Call your carrier's customer service line and ask whether they offer anonymous calling or caller ID blocking. They can tell you whether it is available on your account and whether there is a fee.

Some phone systems — particularly older business phone systems and some VoIP services — do not recognize the *67 command at all. If you use a business phone line or a specialized phone service, ask your phone provider directly what method they use to block caller ID.

Even when *67 works, some recipients have services that unblock private numbers or see the actual number behind the block. Hospitals, police departments, and many businesses use these services. If you call a business and dial *67, they may still see your real number on their end.

Blocking your number on smartphones

On iPhones and Android phones, you can set your phone to hide your number on every call without dialing *67 each time. On an iPhone, go to Settings, then Phone, then Show My Caller ID, and turn it off. On Android, the setting varies by phone model and carrier, but usually appears in Settings under Call Settings or Phone Settings — look for "Caller ID" or "Hide Number" and turn it off.

Once you turn off caller ID on your phone, every call you make will show as private or blocked unless you turn the setting back on. This is different from *67, which hides your number on a single call. If you want to show your number again, you go back to the same setting and turn it on.

Some carriers do not allow you to turn off caller ID in your phone settings. If the option does not appear on your phone, contact your carrier to ask whether they support this feature and how to enable it on your account.

What the recipient sees and what they can do about it

When you call with your number blocked, the person receiving the call sees "Private Number," "Blocked," "Unknown," or a similar message instead of your phone number. They cannot call you back using the normal callback function because there is no number to call back.

Some phone services and apps let people unblock private numbers or see the actual number behind the block. Businesses often use these services. If the person you are calling has one of these services, they may see your real number even though you blocked it.

The recipient can also set their phone to reject all calls from blocked numbers. If they have done this, your call will not go through — it may go to voicemail or be rejected entirely. You will not know whether they rejected it or straightforward did not answer.

Legal limits on blocking your number

Blocking your number is legal in most situations, but there are exceptions. If you call 911 or other emergency services, your number cannot be blocked — emergency systems need your location and number to help you. Some government agencies and courts can also require you to provide your number when you call.

If you use *67 or caller ID blocking to harass someone, threaten them, or commit fraud, that is illegal. The law against harassment and fraud applies whether your number is blocked or not. If someone is harassing you with blocked calls, contact your phone carrier or local police — they can sometimes trace blocked numbers in cases of harassment or threats.

Some states have laws about telemarketing calls and robocalls that require the caller's number to be shown. If you are calling for business purposes, check your state's laws about caller ID requirements.

Alternatives if you want more privacy

If blocking your number is not enough privacy for you, you can use a different phone number entirely. Some people use a second phone line, a Google Voice number, or a temporary phone number service. These give you a different number to call from, so the recipient sees that number instead of your real one.

Google Voice is free and gives you a real phone number that forwards to your actual phone. When you call someone using Google Voice, they see the Google Voice number, not your personal number. You can set up Google Voice on your computer or phone and use it to make calls.

Temporary phone number services let you generate a number that works for a short time — usually a few hours or days. These are useful if you need a number for a one-time call or to verify an account somewhere, but they are not practical for regular use.

Frequently Asked Questions

Can someone trace my number if I block it with *67?

Not easily. When you use *67, the recipient cannot see your number on their phone. However, if they report you to the police or your phone carrier for harassment or threats, law enforcement can request your carrier to provide your number. Emergency services can also see your number even when it is blocked.

Will *67 work on my cell phone?

It works on most U.S. cell phones, but not all. Try dialing *67 before a number on your phone. If your number still shows to the recipient, contact your carrier to ask whether they support anonymous calling and how to enable it.

What happens if I block my number and leave a voicemail?

The voicemail will show as coming from a private or blocked number. The recipient will not see your phone number, but they can still listen to your message and call you back if you leave a callback number in the message itself.

Can I block my number on a business phone line?

It depends on your phone system. Some business phone systems support caller ID blocking, and some do not. Ask your IT department or phone provider whether the feature is available on your business line.

Does blocking my number hide my location?

No. Blocking your caller ID hides only your phone number, not your location. If someone has a service that traces phone locations or if law enforcement gets involved, your location can still be found through your carrier.