How to Block Your Number When Making a Call

To hide your phone number on a single outgoing call in the United States, dial *67 first and then the full number you are calling. The person you reach sees "Blocked", "Private", or "No Caller ID" on their screen instead of your number, and the block covers only that one call.

How do I block my number when making a call?

Blocking your number for one call takes a few seconds and works from any keypad, on a cell phone or a landline.

1. Open the phone keypad, the same screen you use when you dial a number by hand.
2. Enter *67, with no space and no pause after it.
3. Enter the full number including the area code, even when you are calling someone local.
4. Press call.

The prefix is not a setting and it does not stay switched on. You type it again before every call you want hidden. This is the part people miss: tapping a name in your contacts or a line in your recent-calls list dials the plain number, so your caller ID goes out visible. To hide it, dial by hand.

What is the difference between per-call blocking and permanent line blocking?

Blocking your number when making a call comes in two forms, and they behave differently.

• Per-call blocking is the prefix you dial yourself. It needs no setup, it is available on most US lines by default, and it hides one call at a time.
• Permanent line blocking, sometimes called complete or full-time blocking, is set on your account by your phone company. Once it is on, every call leaving that line is hidden until you ask for the setting to be changed.
• With permanent blocking active the prefix works in reverse. Dialing the blocking code changes nothing, because the line is already hidden; you use the unblocking code instead when you want one call to show your number.

How do I hide my caller ID on every call from an iPhone or Android phone?

Both phone systems carry a caller ID switch, and it is separate from the dialing prefix. On an iPhone, open Settings, find the section for the Phone app, and look for the Show My Caller ID switch. On most Android phones, open the phone app itself, open its settings, and look for Caller ID under supplementary or additional call settings.

The switch is not always there, and that is normal rather than a fault. Caller ID presentation is a network feature, so your carrier decides whether the handset can change it. On many prepaid lines, business lines, and lines that run calls over the internet, the switch is missing or greyed out. When that happens the choice lives with the carrier: change it in your online account or ask support to set it on the line.

What to do if the blocking prefix does not work

If you dialed the prefix and the person you called still saw your number, work through these before assuming the line is broken.

• Check the order. The prefix goes first, ahead of the area code, in one continuous string with no pause between.
• Dial the whole number, all ten digits, rather than a shortened local form.
• Dial from the keypad instead of tapping a contact card or a recent call, since those dial the stored number only.
• Turn off Wi-Fi calling and try again on the cellular network. Calls that leave your phone over the internet may ignore the prefix, because it is a code understood by the traditional phone network.
• Remember it is a North American code. A phone roaming in another country usually will not respond to it.
• If none of that helps, blocking is a carrier feature and your carrier can enable it for the line.

Which calls still show your number even when blocking is on?

Caller ID blocking hides your number from an ordinary phone display. It is not anonymity, and several kinds of calls see through it.

• Emergency calls. Your number and location are passed through no matter what block you dialed.
• Toll-free numbers. The business paying for the call receives the calling number through billing records, which are separate from caller ID.
• Calls to people who reject anonymous callers. The call does not connect at all; your caller hears a recording telling them to unblock and call again.
• Text messages. The prefix applies to voice calls only and does nothing to a text you send.

How do I let my number through for just one call?

If your line has permanent blocking and one particular call needs to show your number, dial *82 ahead of the number instead. That reveals your caller ID for that single call and leaves the rest of the line hidden. It is worth knowing before you call a doctor's office, a bank, or anyone who has asked you to call back, since many of them will not accept a hidden number.

What to ask your phone company about blocking your number

If you want this settled once rather than dialed every time, three questions cover it: whether per-call blocking is active on your line, whether permanent line blocking can be turned on for it, and which code releases your number for a single call when permanent blocking is on. Ask about the specific line, not the account, because a family plan can have different settings on different phones.