There are plenty of reasons to not want your phone number showing up when you call someone else. Maybe you just don't like giving it out to strangers, or perhaps you don't want the person you're calling realizing you're ringing from a foreign number.

If you have an iPhone, you can block your number from showing up on other people's caller ID with a simple settings toggle.

First, go to to Settings > Phone and select Show My Caller ID.

Toggle the switch next to Show My Caller ID off.

To turn Caller ID back on again, just come back here and toggle the switch on.

Note that blocking caller ID is a carrier feature. In theory, your carrier might not support it (although we haven't been able to find one who doesn't). If the setting is not there, that's probably why.