What blocking your number means and why you might do it
When you block your number before calling, the person who answers sees "Unknown Caller" or "Blocked Number" instead of your phone number. The call still goes through — they can still answer and talk to you — but they cannot see who is calling them.
People block their numbers for different reasons. You might not want a business to have your personal number. You might be calling a stranger to ask about a used item for sale. You might be calling a government office and prefer not to leave your number on their caller ID. None of these require special permission or setup — the tools are built into your phone.
Blocking your number is different from blocking a contact. When you block a contact, that person cannot reach you at all. When you block your number, you are the one calling, and you are just hiding your number from their view.
Key Takeaways
- You can block your number on most phones by dialing *67 before the number, or by changing a setting in your phone's call settings menu.
- Blocking your number works on regular phone calls but usually does not work on text messages or video calls.
- Some businesses and government offices have systems that ignore blocked numbers and still capture your number, so blocking does not may provide complete privacy.
- If you block your number and the person does not answer, they will not be able to call you back because they have no number to dial.
- Blocking your number is legal in most places, but calling repeatedly with a blocked number to harass someone is not.
Blocking your number on an iPhone
On an iPhone, you have two ways to block your number: do it for a single call, or change your settings so every call hides your number.
For a single call, dial *67 before the phone number you want to call. So if you are calling 555-123-4567, you would dial *67-555-123-4567 and press call. The person who answers will see "Unknown Caller" or "Blocked Number" on their screen.
To block your number on every call, go to Settings, then Phone, then Show My Caller ID. Turn off the toggle next to "Show My Caller ID". Now every call you make will hide your number unless you turn this setting back on. You can turn it back on the same way, or use *82 before a number to unblock just that one call.
Blocking your number on an Android phone
Android phones vary by manufacturer and carrier, so the exact steps depend on which phone you have. The *67 method works on most Android phones the same way it works on iPhone — dial *67 before the number and press call.
To block your number on every call, open the Phone app, tap the three-line menu (usually in the top left or top right), then look for Settings or Call Settings. Find the option for "Caller ID" or "Show My Number" and turn it off. Some phones call this "Hide My Number" or "Block Caller ID". If you cannot find it in the Phone app settings, check your carrier's settings — some carriers manage this through their own app or website.
If you are not sure which phone you have or where the setting is, call your carrier's customer service line and ask them to walk you through it. They can usually change this setting for you over the phone.
When blocking your number does not work
Blocking your number works on regular voice calls, but it has limits. Text messages sent through your phone's regular SMS app will still show your number — blocking only hides your number on calls. Video calls through apps like FaceTime or WhatsApp will also show your number or username, because those apps have their own caller ID systems that ignore the phone-level blocking.
Some businesses and government offices have systems that capture your number even when you block it. Banks, hospitals, and law enforcement agencies often have technology that records the actual number making the call, even if you see "Blocked Number" on your end. If you are calling a place that has this kind of system, blocking your number will not prevent them from seeing who called.
If you do not answer when someone calls you back, they cannot reach you if you blocked your number, because they have no number to dial. This is why blocking your number is risky if you are expecting a return call — the person might not be able to reach you even if they want to.
The difference between blocking your number and using a private number
Blocking your number with *67 and having a private number are almost the same thing from the other person's perspective — they both see "Unknown Caller" or "Blocked Number". The difference is in how it works behind the scenes and how long it lasts.
When you use *67, you are hiding your number for that one call only. When you change your settings to hide your number on every call, you are making your number private by default. Some phone plans also offer a private number as a service through your carrier, which works the same way but is managed by your carrier instead of your phone.
What happens if you call 911 with your number blocked
If you call 911 with your number blocked, the emergency dispatcher will still see your number. Blocking does not work on emergency calls — the system overrides it so dispatchers can locate you and call you back if the line drops. This is true even if you use *67 before dialing 911.
The same is usually true for other emergency numbers and crisis lines. If you are calling a suicide prevention hotline or domestic violence hotline, your number may also be visible to them even if you try to block it, because these services need to be able to reach you if the call disconnects.
Legal and practical reasons to think twice
Blocking your number is legal in most places, but there are situations where it can backfire. If you block your number and call someone repeatedly, that person may report the calls as harassment. Even though you have the right to block your number, using it to harass or threaten someone is illegal.
If you are calling about something that requires follow-up — a job interview, a medical appointment, a service call — blocking your number means they cannot call you back. You might miss an important callback or seem unreliable because you did not leave a way for them to reach you.
If you are trying to build trust with someone, blocking your number can work against you. A person who sees "Unknown Caller" might not answer at all, or they might be suspicious of the call. If you have a legitimate reason to call, leaving your number visible is usually the better choice.
Frequently Asked Questions
Can someone trace my number if I block it?
Not through normal means. If you block your number, the person cannot see it on their phone. However, law enforcement can trace blocked calls if they have a warrant, and some businesses have systems that capture the actual number even when it is blocked. For most everyday situations, blocking your number prevents the average person from seeing or tracing it.
Does *67 work on all phone carriers?
*67 works on most carriers in the United States, including Verizon, AT&T, T-Mobile, and most smaller carriers. Some carriers or phone systems may use a different code — if *67 does not work, call your carrier to ask what code they use or how to block your number on their network.
If I block my number, can the person still leave me a voicemail?
Yes. If they do not answer, your call goes to voicemail as usual. They will hear your voice in the message, but they will not have your number to call back unless you give it to them in the message itself.
What is the difference between *67 and *82?
*67 blocks your number for one call. *82 unblocks your number for one call if you have your number blocked on all calls by default. So if you have set your phone to hide your number on every call, you can use *82 before a specific number to show your number just for that call.
Will blocking my number work if I call a business that has caller ID?
The business will see "Unknown Caller" or "Blocked Number" on their end, but many businesses have phone systems that record the actual number anyway. Your number will be hidden from the person who answers, but the business may still have a record of it in their system.