How can I block unknown callers on my iPhone?

Enable the "Silence Unknown Callers" feature by navigating to Settings > Phone and toggling on Silence Unknown Callers. This will send calls from unknown numbers directly to voicemail. ([consumerreports.org](https://www.consumerreports.org/robocalls/how-to-block-robocalls-how-to-protect-yourself))

What services do major U.S. carriers offer to block robocalls?

Major carriers provide services like AT&T's ActiveArmor, Verizon's Call Filter, and T-Mobile's Scam Shield to identify and block potential spam calls. ([malwarebytes.com](https://www.malwarebytes.com/cybersecurity/basics/scam-likely-calls))

Is the National Do Not Call Registry effective in reducing unwanted calls?

Registering with the National Do Not Call Registry can reduce calls from legitimate telemarketers but does not block calls from scammers or robocallers. (consumer.ftc.gov)

Effective Strategies to Reduce Telemarketing Calls on Your Mobile Phone

Telemarketing calls are a persistent nuisance for many mobile phone users in the United States. While it's challenging to eliminate them entirely, several effective strategies can significantly reduce their frequency.

Why Are Telemarketing Calls So Persistent?

Despite the Federal Trade Commission's National Do Not Call Registry, unwanted calls continue to plague consumers. This is partly due to advancements in technology that allow robocallers to spoof numbers and bypass traditional call-blocking methods. (kiplinger.com)

How Can Built-In Smartphone Features Help Block Unwanted Calls?

Modern smartphones offer built-in features to help manage unwanted calls:

iPhone Users: Enable the "Silence Unknown Callers" feature by navigating to Settings > Phone and toggling on Silence Unknown Callers. This will send calls from unknown numbers directly to voicemail. (consumerreports.org)
Android Users: Activate the "Block Calls From Unidentified Callers" option by going to the Phone app > Settings > Blocked Numbers and enabling the feature. (consumerreports.org)

What Role Do Carrier Services Play in Reducing Robocalls?

Major U.S. carriers have implemented services to combat robocalls:

AT&T: Offers ActiveArmor, which identifies and blocks potential spam calls.
Verizon: Provides Call Filter, alerting users to potential spam calls.
T-Mobile: Features Scam Shield, which includes scam call blocking and caller ID.

These services often require activation and may come with additional fees. (malwarebytes.com)

How Do Third-Party Call-Blocking Apps Enhance Call Protection?

Third-party apps can offer more robust protection against unwanted calls:

RoboKiller: Recognized as a leading solution, RoboKiller uses advanced algorithms and a vast database to identify and block spam calls effectively. (kiplinger.com)
Hiya: Provides real-time spam detection and caller ID features.
Truecaller: Offers a comprehensive database to identify and block spam calls.

These apps often require a subscription but can significantly reduce unwanted calls. (reporttelemarketer.com)

How Effective Is the National Do Not Call Registry?

Registering your number with the National Do Not Call Registry can reduce calls from legitimate telemarketers. However, it does not block calls from scammers or robocallers. To register, visit donotcall.gov. (consumer.ftc.gov)

What Are Some Additional Tips to Minimize Unwanted Calls?

Avoid Sharing Your Number Publicly: Be cautious about where you share your phone number to prevent it from being added to marketing lists.
Use Temporary Numbers: For online sign-ups or services, consider using a temporary or disposable number.
Report Unwanted Calls: If you receive a scam call, report it to the Federal Communications Commission (FCC) to help authorities track and combat these calls. (consumer.ftc.gov)

By implementing these strategies, you can significantly reduce the number of telemarketing calls you receive, leading to a more peaceful and secure mobile experience.