Get Your Free Guide to Blocking Your Telephone Number

Understanding Telephone Number Blocking Basics

Blocking your telephone number means preventing your number from appearing on the recipient's caller ID when you make an outgoing call. When you block your number, the person receiving your call will typically see "Unknown," "Blocked," "Private," or "Restricted" instead of your actual phone number. This feature exists because many people want privacy for certain calls, whether for personal safety, business confidentiality, or simply preferring not to share their contact information with every call recipient.

The Federal Communications Commission (FCC) recognizes caller ID blocking as a standard telecommunications feature. According to the FCC's regulations, telephone service providers must offer this feature to customers at no charge. This means whether you use a landline, mobile phone, or VoIP service, your provider should make blocking available to you without requiring any special subscription or payment.

There are two main types of number blocking: per-call blocking, where you block your number on individual calls, and permanent blocking, where your number remains blocked on all outgoing calls unless you disable it. Different phone services and devices offer different methods for using these features. Understanding which option you need depends on your situation—whether you want to block your number occasionally or for all calls you make.

It's important to know that blocking your number may affect how certain calls are received. Some businesses, government agencies, and automated systems may reject or handle blocked calls differently. Healthcare providers, banks, and other institutions sometimes need to see caller ID information to process calls appropriately. Additionally, emergency calls to 911 will transmit your number regardless of blocking settings, as emergency responders need this information to locate you.

Practical Takeaway: Before using number blocking, consider why you need it and which type (per-call or permanent) matches your needs. Remember that blocked calls may be treated differently by some recipients, and emergency services will always receive your number.

Methods for Blocking Your Number on Different Phone Types

The process for blocking your number differs depending on what type of phone service you use. Mobile phones, landlines, and internet-based calling services each have their own systems and options. Learning the specific method for your phone type takes only a few minutes and requires no technical expertise.

For most smartphones and mobile phones, per-call blocking is simple. On iPhones, you dial *67 before the number you want to call. On Android phones and most other mobile devices, you also use *67 as a prefix. This is the standard code in the United States and Canada. After dialing *67, enter the phone number normally. The recipient will see a blocked caller ID. If you want to block your number permanently on a mobile phone, you can usually access this through your phone's settings menu, though the exact location varies by device. Some phones have it under "Call Settings," while others list it under "Phone" or "More Settings."

For landline phones, the blocking method depends on whether you have a traditional landline from a telephone company or a digital phone service. With traditional landlines, you typically dial *67 before the number, just like with mobile phones. However, some landline providers offer a feature called "Calling Line Identification Restriction" (CLIR) that you can enable through your account settings to block your number on all calls. To find out if your landline provider offers this, you can call their customer service line and ask about permanent call blocking options.

VoIP services like Google Voice, Skype, Vonage, and others handle number blocking through their app settings or online account portals. With Google Voice, you can adjust caller ID settings in your account preferences. Skype allows you to control whether your number displays in your account settings. Each VoIP provider has slightly different procedures, so checking your service's help section or contacting their support team ensures you're using the correct method.

Practical Takeaway: The *67 prefix works for most calls from mobile phones and traditional landlines in the U.S. For permanent blocking or VoIP services, access your account settings or contact your provider directly for specific instructions.

Step-by-Step Instructions for Activating Number Blocking

This section walks through the actual steps for blocking your number, whether you're making a single call with your number blocked or setting up permanent blocking on your account.

For a single blocked call on a mobile phone: Pick up your phone and unlock it. Open the dialer or phone app. Dial the following sequence: *67, then the area code and phone number you want to call. Press the call button. The person receiving your call will see "Blocked" or "Unknown" instead of your number. This works on both iOS and Android devices in the United States.

For permanent blocking on a mobile phone: Open your phone's Settings app. Look for "Phone" settings or "Call Settings" (this varies by device). Find the option labeled "Caller ID," "Show My Caller ID," or similar language. Toggle this setting to "Off" or "Disabled." If your phone doesn't have this option in Settings, contact your mobile carrier's customer service. They can often enable permanent blocking through your account.

For permanent blocking on a traditional landline: Call your phone company's customer service number, which appears on your bill. Tell them you want to enable permanent caller ID blocking or CLIR for your account. Some companies may call this "Anonymous Call Rejection" or use other terminology. Ask them to confirm it's been activated. You may receive a confirmation through email or mail.

For VoIP services: Log into your account on the provider's website or open their mobile app. Navigate to Settings or Account Settings. Look for sections labeled "Caller ID," "Privacy," or "Call Settings." Find the option to hide or block your number. Change this setting as desired. Save your changes. Some services may require 24 hours for changes to take effect.

Practical Takeaway: The *67 method is quickest for occasional blocked calls. For permanent blocking, you'll need to access your phone's settings or contact your provider, which takes 5-15 minutes depending on your service type.

Situations Where Number Blocking Is Most Useful

Number blocking has many legitimate uses. Understanding common situations where people use this feature can help you decide if it's right for your circumstances.

Personal safety is one primary reason people block their numbers. If you're calling someone you don't have an established relationship with—such as when responding to a job listing, joining a new organization, or contacting a service provider for the first time—you may want to protect your personal number from being shared or sold. By blocking your number initially, you can gauge whether the other person is legitimate before sharing your contact information.

Privacy during business calls is another common use. Real estate agents, home service providers, insurance agents, and others who make many outgoing calls sometimes block their numbers to avoid callbacks to their personal phones. This keeps their business and personal communications separate. Consultants and freelancers working with multiple clients often block their numbers to avoid mixing client databases.

Medical and sensitive situations sometimes require number blocking. Therapists, social workers, and others in helping professions may block their numbers when calling clients from personal phones. Similarly, people calling to discuss sensitive matters—addiction recovery programs, domestic violence resources, mental health services—may block their numbers to protect their privacy.

Testing caller ID systems and phone lines is a technical use. IT professionals and telecommunications workers sometimes block their numbers when testing whether phone systems are functioning correctly or when checking how calls are being routed through a network.

Protecting privacy from ex-partners or estranged family members is another legitimate reason. When someone has legitimate reasons to maintain distance but needs to make occasional calls, blocking their number adds a layer of privacy protection.

Practical Takeaway: Blocking is most useful when you want to initiate contact with someone while maintaining your privacy, or when separating personal and professional communications. It's less useful for ongoing relationships where the other person typically expects to see your number.

Important Limitations and Things Number Blocking Won't Do

While number blocking is a useful privacy tool, it has important limits that anyone considering using it should understand.

Number blocking does not prevent call tracing. Law enforcement and authorized agencies can trace blocked calls through telecommunications infrastructure if needed for legitimate purposes. This means blocking your number offers privacy from the average caller, but not from determined investigators or authorities.

Blocking your number may cause some calls to be rejected or handled differently. Many businesses have systems that automatically filter or route blocked calls.