What Does *67 Do? Unlocking The Mystery Behind This Star Code
Have you ever wondered, "What is star 67 do?" You’ve seen the little asterisk and the numbers on your phone keypad, maybe even typed it before a call out of curiosity or a vague memory from a friend. In an age of spam calls, robocalls, and unwanted outreach, the desire for a simple, free way to control your caller ID is stronger than ever. That’s exactly where *67 comes in. It’s not a secret code to unlock hidden features or a backdoor to free calls—it’s a straightforward, powerful tool for caller ID blocking that has been a staple of telephony for decades.
This guide will completely demystify *67. We’ll move beyond the basic "it blocks your number" answer to explore its fascinating history, precise mechanics, practical applications, significant limitations, and its place in today’s complex communication landscape. Whether you’re a privacy-conscious individual, a small business owner, or just someone tired of seeing unknown numbers flash on your screen, understanding *67 is a fundamental piece of digital self-defense. Let’s dive deep and answer the question once and for all: what does star 67 do, and how can you use it effectively?
The Core Function: How *67 Blocks Your Caller ID
At its heart, the answer to "what is star 67 do?" is beautifully simple. When you dial *67 followed by the phone number you wish to call, it instructs your telephone service provider to temporarily suppress your outgoing caller ID information for that specific call. Instead of your name and phone number appearing on the recipient's caller ID display, they will typically see one of the following:
- "Private Number"
- "Anonymous Call"
- "Blocked"
- "No Caller ID"
- "Unknown"
The key word here is temporarily. The effect lasts only for that single call instance. Your caller ID will revert to its normal, public state for all subsequent calls. This is a per-call basis blocking service, not a permanent setting change on your line (though many carriers offer that as a separate, paid feature).
The Technical Dance: What Happens Behind the Scenes?
When you make a standard call, your phone sends a signal to your carrier's switch, which includes your calling party number (CPN)—your caller ID data. This data is then transmitted through the network to the recipient's carrier and ultimately displayed on their device.
Dialing *67 inserts a special code—a vertical service code (VSC)—into that initial signal. Your carrier's switch interprets this code and strips the CPN from the call setup information before it leaves their network. To the rest of the telephone system and the recipient's phone, the call appears to be originating from a line with no associated caller ID. It’s a clean, network-level redaction. This process works on both landline (POTS - Plain Old Telephone Service) and most mobile/cellular networks, as they all rely on the same SS7 (Signaling System No. 7) protocol infrastructure for call routing and caller data.
How to Use *67: A Step-by-Step Guide
Using *67 is incredibly straightforward, but the exact sequence matters.
- Pick up your phone to get a dial tone (on a landline) or open your phone app (on mobile).
- Dial *67. You should hear a confirmation tone or see a message on your screen (on mobile).
- Immediately dial the full 10-digit phone number you wish to call (area code + number). Do not pause for too long between *67 and the number.
- Place the call as you normally would.
Example: To call 555-123-4567 with a blocked ID, you would dial: *67 555-123-4567 and then hit send/call.
Important: You must dial *67 before every single call you want to be private. It does not "stick." There is no "turn on" and "turn off." It is a prefix you add to the number each time.
A Brief History: The Origins of Star Codes and Privacy
But 67 didn’t just appear out of thin air. To fully understand "what is star 67 do," we need a quick trip back in telephony history. The asterisk () and pound (#) keys on your phone were originally installed in the 1960s for signaling and service activation. They were placeholders for future features—a visionary move by AT&T’s Bell System. These became known as "star codes" or vertical service codes.
The need for caller ID blocking emerged in the 1980s and 1990s as caller ID services (like *69 for call return) became commercially popular. While useful, they also created a privacy dilemma. Businesses, doctors, and individuals who needed to make sensitive calls without revealing their number demanded a solution. *67 was the industry's answer, standardized across North America as part of the Custom Local Area Signaling Services (CLASS) package. Its deployment was solidified in the 1990s, and it remains a universal, carrier-agnostic feature to this day, a testament to its simple and effective design.
The Crucial Limitations: What *67 Does NOT Do
Understanding what *67 does is only half the battle. Knowing its significant limitations is critical to using it correctly and avoiding false assumptions. Here’s where *67 falls short:
- It Does NOT Work for Toll-Free Numbers (800, 888, 877, etc.): The owners of toll-free numbers pay for the call, and part of that service includes receiving the caller's phone number for billing, analytics, and callback purposes. Federal regulations also often require ANI (Automatic Number Identification) for such calls. Your number will be visible.
- It Does NOT Block Your Number from 911 or Emergency Services: In an emergency, your location and number are automatically transmitted to the Public Safety Answering Point (PSAP). Using *67 would be dangerous and is typically prohibited or ineffective for 911 calls.
- It Does NOT Guarantee Anonymity from Law Enforcement or Your Carrier: Your carrier still has a record of the call and the number you dialed. With a subpoena or court order, law enforcement can access your call records. *67 provides privacy from the recipient, not from the authorities or your phone company.
- It Does NOT Work Internationally (in most cases): The *67 code is a North American Numbering Plan (NANP) standard. Calling a number in Europe, Asia, or elsewhere will likely not trigger the blocking mechanism. You must use the local blocking code for that country, if one exists (e.g., the UK uses 141).
- It Does NOT Block Your Number from VoIP and Smartphone Apps: Services like Google Voice, Skype, WhatsApp, and many business communication apps have their own caller ID systems. Using *67 on a traditional line to call a Google Voice number may not block your ID from the Google Voice user's perspective, as the call may be routed through different systems.
- It Does NOT Prevent Call Tracing or Callback: If the person you call uses a call-tracing service (*57 in the US/Canada) immediately after your blocked call, they can often obtain your number from the carrier (though they usually have to pay a fee and involve law enforcement for action). They also cannot simply hit "call back" on their phone to reach you.
Practical Use Cases: When and Why to Use *67
Now that we know the "how" and the "what not," let's explore the smart, practical applications. Using *67 isn't just for secretive calls; it's a tool for situational privacy.
- Returning a Missed Call from an Unknown Number: Saw a missed call from "Unknown" or "No Caller ID"? Before calling back, use *67. This protects you if the number is a spam trap designed to confirm active numbers for more spam.
- Calling a Business for a Sensitive Inquiry: Need to ask about a personal health matter, a legal issue, or a financial service? Using *67 prevents your number from being added to that business's marketing call list.
- Contacting Someone You Prefer Not to Have Your Number: Perhaps you're calling a landlord about a rental, a seller on Craigslist, or an old acquaintance. *67 gives you control over your personal contact information.
- Whistleblowing or Reporting Anonymously: While not legally protected like some dedicated hotlines, *67 can add a layer of separation when reporting suspicious activity to a non-emergency line.
- Testing Business Lines: Small business owners can use *67 to see if their own business line displays correctly to customers by calling from a personal line with *67 enabled.
Actionable Tips for Effective *67 Use
- Test It First: Call a friend or family member with *67 to confirm it works on your specific carrier and phone model. Have them confirm what appears on their screen.
- Dial Perfectly: Ensure there is no pause between *67 and the 10-digit number. A pause can cause the code to be ignored.
- Know Your Carrier's Quirks: Some carriers may require you to dial *67, wait for a second dial tone, and then dial the number. Check your carrier's support page for exact instructions.
- Have a Backup Plan: For critical anonymous calls, consider using a disposable VoIP number app (like Google Voice, Burner, or Hushed) which offers more robust, app-based control over caller ID.
- Never Use for Harassment: Using *67 to make threatening or harassing calls does not make you anonymous to law enforcement and is illegal. This tool is for privacy, not abuse.
The Privacy Landscape: *67 vs. Modern Solutions
In today's world, *67 is a legacy tool from a simpler telephony era. It operates at the network level on traditional phone lines. Modern privacy challenges come from smartphone apps, internet-based calling, and data harvesting. This is where *67's limitations become most apparent.
- Smartphone Native Settings: Both iOS and Android have settings to "Hide Caller ID" for all outgoing calls. This is a permanent line setting, more convenient than dialing *67 each time, but it also blocks your ID on all calls, including to friends and family, which is often undesirable.
- Carrier Services: Many carriers now offer a "Per-Call Blocking" service that is essentially *67, and a "Per-Line Blocking" service that permanently hides your number (often for a monthly fee).
- Third-Party Apps: Apps like Google Voice provide a separate phone number. You can make calls from this number, and your primary personal number remains completely hidden. This is a more flexible solution for frequent needs.
- The Robocall Arms Race: Spoofing technology allows bad actors to fake any caller ID. *67 does nothing against this. The fight against spam now relies on carrier-level analytics, STIR/SHAKEN call authentication protocols, and FCC regulations, not individual blocking codes.
Addressing Common Questions and Myths
*Q: Does 67 work on iPhones and Android phones?
A: Yes, absolutely. *67 is a carrier network feature, not a phone-specific one. It works on any device that can make a standard cellular or landline call.
*Q: Is 67 free?
A: In the United States and Canada, yes. *67 is a standard, free vertical service code. However, always check with your specific carrier, as some prepaid or international plans may have different terms.
*Q: Will 67 block my number from someone who has a private or blocked number calling me?
A: No. Caller ID blocking is directional. *67 only affects the outgoing caller ID from your call. It has no impact on incoming calls. If someone with a blocked number calls you, you will still see "Blocked" or "Unknown."
*Q: Can I use 67 to call 911?
A: No, and you should never try. Emergency services require your accurate location and number. Using *67 may prevent your call from being properly routed or your location from being displayed, which could be fatal in an emergency.
*Q: Does 67 work for text messages (SMS)?
A: No. *67 is exclusively for voice calls. There is no standard code to block your number from a text message. Your number will always be visible in an SMS/MMS.
The Future of Caller Privacy and the Role of *67
As communication shifts entirely to IP-based networks (VoIP, messaging apps, video calls), the old PSTN (Public Switched Telephone Network) codes like *67 feel increasingly archaic. Their relevance is tied to the persistence of traditional phone number calling.
However, *67 is not disappearing tomorrow. Millions of landlines and cellular calls still use the traditional SS7 framework. It remains a universal fallback, a piece of telephony knowledge everyone should possess. Its enduring value lies in its simplicity, zero cost, and universal compatibility within its operational scope.
The future of privacy will involve:
- Widespread STIR/SHAKEN adoption to combat spoofing.
- Default call blocking and labeling by carriers and OS makers (like Google's "Verified Calls" and Apple's "Silence Unknown Callers").
- Decoupling identity from the phone number through more use of app-based identities.
- Stronger regulations on data sharing by telecom companies.
Yet, in this future, *67 will likely still exist as a legacy compatibility feature—a simple command that works on any phone, anywhere in North America, without needing an app update or a new OS version. It’s the digital equivalent of a reliable, old screwdriver in a toolbox full of fancy power tools.
Conclusion: Mastering a Fundamental Tool
So, what does star 67 do? It is your on-demand, per-call switch for caller ID anonymity on the traditional telephone network. It’s a free, easy-to-use tool born from the early days of telephony innovation that continues to serve a vital privacy function in 2024. By understanding its precise function—temporarily suppressing your number for a single call—and its well-defined boundaries—it fails for toll-free, emergency, and most international calls—you can wield it effectively.
Don't think of *67 as a magic invisibility cloak. Think of it as a discreet cover for your phone number when you need it for a specific, legitimate purpose. In a world where your phone number is a key to marketing lists, data profiles, and unwanted contact, having this simple code in your repertoire is a small but significant act of reclaiming control. Test it, understand its limits, use it wisely, and pair it with your smartphone's built-in spam filters and a healthy dose of skepticism for unknown callers. You've now unlocked the complete mystery of star 67.
