How to Block Your Telephone Number When Making Calls

Blocking your phone number so it doesn't appear on the recipient's caller ID is one of those features most people don't think about until they suddenly need it. Whether you're calling a business, protecting your privacy, or just don't want your personal number saved, there are several reliable ways to hide your number — and the method that works best depends on your device, carrier, and how often you need the feature.

What "Blocking" Your Number Actually Means

When you block your telephone number, you're instructing the phone network to withhold your Caller ID information from the person you're calling. Instead of seeing your number, they'll typically see "Private Number," "Blocked," "Unknown," or "No Caller ID" — the exact label varies by carrier and the recipient's device.

This works through a standard telephony feature called CLIR (Calling Line Identification Restriction). It's supported across virtually all mobile and landline networks globally, though how you activate it differs depending on your setup.

It's worth understanding one important distinction: blocking your number is not the same as being untraceable. Your carrier always knows what number placed the call. CLIR only controls what the recipient sees. Law enforcement, emergency services, and your carrier can still identify your number when legally required.

Method 1: Use a Per-Call Code

The quickest way to block your number for a single call is to dial a prefix code before the phone number. In the US and Canada, that code is *67.

How it works:

• Dial *67 followed immediately by the full number, including area code
• Example: *67 555 867 5309
• Your number will appear as blocked for that specific call only
• Your next call without the prefix will show your number normally

In the UK, the equivalent code is 141. In Australia, it's 1831. Other countries use similar short-code prefixes — if you're outside North America, a quick search for "CLIR code [your country]" will confirm the right digits.

This method requires no settings changes and works on virtually any phone — smartphone or basic handset.

Method 2: Change Your Default Caller ID Settings

If you want your number hidden on every call without manually entering a code each time, you can configure your phone's settings to block by default.

On iPhone (iOS)

Go to Settings → Phone → Show My Caller ID and toggle it off. This applies globally to all outgoing calls until you turn it back on.

On Android

The path varies slightly by manufacturer, but generally: Phone app → Settings (or three-dot menu) → Calls → Additional Settings → Caller ID → Hide Number

Some Android skins (Samsung One UI, for example) label this slightly differently, but the option exists in the same general area.

Important caveat 📱

Some carriers override this setting. If you toggle off Caller ID in your phone's settings and your number still shows, your carrier may be ignoring the device-level instruction. In that case, you'll need to contact your carrier directly to enable CLIR at the account level — more on that below.

Method 3: Enable Restrictions Through Your Carrier

Most mobile and landline carriers offer caller ID blocking as an account-level feature, separate from anything you configure on your device. This is the most reliable method because it's enforced at the network level, not just by your handset.

Options typically include:

• Permanent CLIR — your number is always withheld by default
• Per-call override — you can unblock your number for specific calls using a code like *82 (in the US)

Contact your carrier's support line or check your online account portal to see what options are available. Some carriers include this free; others may apply it as a standard feature with no charge.

Variables That Affect How This Works

VoIP and App-Based Calls Are a Different Story

If you're making calls through apps like WhatsApp, FaceTime, Google Meet, Zoom, or Signal, the CLIR system doesn't apply in the same way. These apps use VoIP (Voice over Internet Protocol) and typically display your registered account name or number rather than a traditional phone number.

Hiding your identity on VoIP platforms usually means:

• Using a secondary account
• Using a burner number app (apps that provide disposable phone numbers)
• Adjusting privacy settings within the specific app

The *67 trick won't help on a WhatsApp call — those are routed entirely differently from standard cellular calls.

When Blocked Numbers Don't Stay Blocked 🔒

Some recipients can and do reject calls from blocked numbers entirely. Businesses, medical offices, and individuals using call-screening apps may automatically decline any call where Caller ID is withheld. If you consistently can't get through, a blocked Caller ID may be why — and in those cases, you'd need to either unblock your number for that call or use an alternate contact method.

There's also the question of number spoofing, which is a different concept entirely — that involves replacing your real number with a fake one, and is heavily regulated (and in most contexts, illegal) under laws like the US Truth in Caller ID Act.

Your Setup Is the Key Variable

The right approach for hiding your number comes down to specifics that vary from person to person: what phone you're using, who your carrier is, whether you're making cellular or VoIP calls, and how often you need the feature. A one-off private call to a business and a permanent need for number privacy call for entirely different configurations — and what works on one carrier or device may behave differently on another.