How to Block Your Number on iPhone Before Making a Call
Privacy during phone calls matters more than most people realize. Whether you're calling a business, reaching out to someone you don't know well, or simply want more control over what information you share, knowing how to hide your caller ID on an iPhone is a genuinely useful skill. The good news: iPhone gives you more than one way to do it.
What "Blocking Your Number" Actually Means
When people ask how to block their number on iPhone, they're talking about caller ID suppression — preventing the person you're calling from seeing your phone number. Instead of your number, they'll typically see "No Caller ID," "Private Number," or "Unknown" on their screen.
This is different from blocking someone else's calls to you. Hiding your number is an outbound privacy tool. It works at the network level, and your carrier plays a role in whether it functions consistently.
Method 1: Hide Your Number for Every Call (System-Wide Setting)
If you want your number hidden by default on all outgoing calls, iPhone has a built-in toggle for this.
Steps:
- Open Settings
- Tap Phone
- Tap Show My Caller ID
- Toggle it off
When this setting is off, every call you make will go out without displaying your number — automatically, with no extra steps needed per call.
⚠️ One important caveat: this setting depends on your carrier supporting it. Most major carriers in the US, UK, and elsewhere honor this toggle, but some prepaid plans or regional carriers may not. If you flip the switch and your number still shows up, your carrier may be overriding the setting. A quick call to your carrier's support line can confirm whether suppression is available on your plan.
Method 2: Hide Your Number for a Single Call (Per-Call Code)
If you want your number visible most of the time but private for specific calls, you don't need to dig into Settings every time. You can use a prefix code directly in the dial pad.
In the US and Canada: Dial *67 before the phone number.
Example: *67 555-867-5309
The call goes through normally, but your number is masked for that one call only. Your caller ID settings in the app remain unchanged.
In the UK and most of Europe: Use #31# before the number.
Example: #31#07700900123
Different regions use different codes, so if you're traveling internationally or calling abroad, it's worth checking the prefix used in that country.
Method 3: Temporarily Show Your Number When It's Normally Hidden
The reverse also works. If you've turned off caller ID globally using the Settings toggle, you can un-suppress your number for a single call using *82 (US/Canada) before dialing.
This is useful because some people and businesses won't answer calls from unknown numbers — and some voicemail systems won't accept them. Having the ability to override your own suppression per call gives you flexibility.
What Affects Whether This Works 📱
Caller ID suppression sounds simple, but several variables determine how reliably it works in practice:
| Factor | What It Affects |
|---|---|
| Carrier plan type | Some prepaid or MVNO plans don't support suppression |
| Call destination | Toll-free numbers (800, 888, etc.) often bypass suppression |
| VoIP or internet calls | Apps like FaceTime Audio or WhatsApp have their own caller ID rules |
| International routing | Cross-border calls may not honor suppression codes |
| Emergency services | 911 and similar services always receive your number regardless |
That last point is a legal requirement, not a technical limitation. No consumer method of hiding your number prevents emergency services from identifying you — and that's intentional.
How This Works with Third-Party Calling Apps
If you make calls through WhatsApp, FaceTime, Skype, Google Voice, or similar apps, the iPhone's built-in caller ID settings don't apply. Each app manages its own identity and caller presentation.
- Google Voice lets you use a separate number, which is itself a form of number masking
- WhatsApp shows your WhatsApp-linked number to the other party
- FaceTime shows the Apple ID email or phone number associated with your account
- Skype has its own caller ID settings within the app
If privacy across VoIP calls matters to you, you'll need to look at each app's individual settings rather than relying on the iPhone's phone settings.
One Behavior Worth Knowing
Some recipients have apps or services that attempt to reverse-identify suppressed numbers using third-party databases. This doesn't mean your number is being transmitted — it means some services try to match call patterns or account data to make a guess. It's unreliable and not something you can control on your end, but it's worth knowing the system isn't completely bulletproof from an identification standpoint.
The Variables That Determine What Works for You
The right method depends on how often you need privacy, which type of calls you're making (cellular vs. VoIP), where you're calling from geographically, and what your carrier plan actually supports. Someone on a standard postpaid plan making domestic calls has a different experience than someone on a prepaid plan calling internationally through a VoIP app.
Understanding your own call habits and confirming your carrier's support for caller ID suppression is the piece that turns this from general knowledge into something that actually works reliably for your specific situation.