How to Block and Stop Spam Calls on Your Phone Permanently

9 ways to block spam calls on iPhone, Android & landline

You can block spam calls by silencing all unknown callers on your phone, installing spam-filtering apps, and registering your number on the national Do Not Call Registry. These spam-blocking methods can help stop scam calls, robocalls, and unwanted calls from getting through to your phone.

Calls aren’t the only spam you can get, so it’s also important to know how to stop spam emails and spam text messages. And if you’re getting scammed on WhatsApp, you can block numbers directly in the app.

But first, follow these 9 steps to shield your phone from nuisance callers:

1. Block individual unknown callers via your phone settings

If you sometimes need to take calls from people you don’t know, you should opt to block callers individually or use a different spam-blocking method instead of stopping all unknown callers.

Use "Block this Caller" on iPhone

You can usually find individual spam caller numbers on your iPhone’s Recents list, but they might also be in Contacts, Favorites, or Voicemail, depending on your contact history with the number.

Here’s how to block an individual phone number on an iPhone:

1. Go to the Phone app > find the number you want to block > tap the i icon next to it.

2. Scroll and tap Block this Caller > Block Contact.

   

Report and block a caller on Android

Here’s how to block individual numbers on your Android by marking them as spam:

1. Open the Phone app > select Recents > tap the number you want to block > tap the i icon.

2. Tap Report > select the spam call type associated with the number (some Androids may not have this step) > tap OK > Block.

   

2. Stop all unknown callers

If you're receiving frequent spam calls, filtering unknown numbers can help. However, this may also block legitimate calls from new contacts or service providers. And while it can reduce phone spoofing attacks, scammers can still spoof trusted contacts or legitimate businesses, so stay vigilant.

Silence unknown callers on iPhone

When you silence unknown callers on an iPhone, only numbers in your Contacts, or that you’ve previously engaged with, can call you.

Here’s how to filter and block all unknown and private numbers on an iPhone:

1. Go to Settings > scroll and tap Phone > Silence Unknown Callers.

2. Slide the toggle On.

Bear in mind that even after you silence unknown callers, your iPhone will still allow calls from numbers saved in your WhatsApp contacts list and other secure messaging apps.

Stop all spam callers on Android

The Android caller ID and spam protection feature provides information about unknown callers and businesses while warning you about potential spam calls. Typically enabled by default, it also allows you to block suspicious numbers entirely for added security.

Here’s how to turn on the caller ID and spam protection feature:

1. Open the Phone app > tap the three dots menu > select Settings > Spam and Call Screen.

   

2. Turn on Caller ID and spam protection > tap Block numbers > toggle on Block spam and scam calls.

   

Once you do this, you’ll only see the filtered calls in your Call History or Voicemail — they won't appear as missed calls.

Use Smart Call scanner on Samsung

Samsung's Smart Call feature detects potential spam or fraudulent calls, displaying warnings to alert users. Available on most Samsung devices with One UI 1.1 or later, it uses Samsung's data and Google services to automatically block or flag suspicious calls, minimizing unwanted interruptions.

Here’s how to block spam calls using Samsung's Smart Call feature:

1. Open the Phone app > Tap the three dots menu > Select Settings > Block numbers.

2. Slide the toggle under Block calls from unknown numbers to on.

Samsung's Smart Call feature may occasionally flag legitimate calls — its effectiveness varies by region, phone carrier, and data connection. If you encounter problems with the feature, try clearing app data or running an Android system update on your device.

3. Dial *77 to stop all no caller ID calls

Dialing *77 into your keypad will activate the call-blocking feature that stops incoming calls without a caller ID. The feature is available on most landlines and some mobile networks, but check with your service provider if you’re unsure.

After you dial *77 on your cell phone or landline, you should hear an automated message confirming that calls from private numbers are now blocked. Spam callers using an anonymous number will receive a recorded message that you don't accept calls from private numbers.

Dialing *77 is ideal for users who receive a high volume of spam or unwanted calls from private numbers and prefer to block them altogether. However, blocking private numbers may also block important calls, like those from healthcare providers. You can typically disable this setting by dialing *87.

4. Use *61 to block your last unwanted caller

The *61 call-blocking service is available on digital home phones with AT&T and is available through some other providers. Check with your provider to confirm if this service is available to you.

The *61 system only blocks the most recent caller, so you need to call *61 directly after each unwanted call. After dialing *61, the system will confirm that the last caller’s number has been blocked. With AT&T, you can block up to 100 numbers.

5. Block suspected scam calls with #662#

T-Mobile’s **#662#** Scam Block feature automatically blocks calls identified as potential scams. Available on many mobile plans (but not landlines), it detects and filters out suspicious calls based on known scam patterns. Blocked calls won’t ring or appear in your call log.

Here’s how to activate Scam Block:

1. Open your keypad and dial #662# on your mobile phone.

2. You should receive a confirmation message or notification stating that Scam Block has been activated.

3. Once activated, Scam Block will filter incoming calls.

Dial #632# to deactivate the Scam Block; you can turn it on or off as needed.

Like other call blockers, Scam Block relies on an up-to-date database to work efficiently, and it may sometimes block legitimate calls in error.

6. Register your number on the Do Not Call Registry

Telemarketers rely on public contact lists to make their calls, but the Do Not Call Registry removes your number from these lists. You can register for free by calling 1-888-382-1222 (voice) or 1-866-290-4236 (TTY), or by signing up online.

Here’s how to get on the Do Not Call Registry online:

1. Go to the National Do Not Call Registry website.

2. Choose Register Your Phone > Register Here > enter up to three phone numbers and your email address > Submit.

3. Open the confirmation email within 72 hours of your submission and follow the steps to complete the process.

   

7. Use your cell phone carrier’s spam-blocking tools

You can stop spam calls using your cell phone carrier's spam-blocking services. Carriers like AT&T and Verizon offer free and paid tools that use machine learning to identify and block unwanted calls. These tools display warnings like “Spam Risk” or “Scam Likely” on incoming calls.

Activating these features via your carrier's app or your account settings can limit the amount of spam calls you receive on your device. Additionally, you can contact your cell phone provider to request telemarketer blocking services or check for a Do Not Call option.

Some features like customized blocking lists may be available but typically incur additional fees.

T-Mobile spam block tool

If you have a device with T-Mobile, you can use the Scam Shield basic service to help protect your identity.

Here’s how to use T-Mobile's Scam Shield to stop spam calls:

1. Download and log in to the T-Mobile app > toggle Scam Shield to on.

2. Go to the app settings to customize your block list and adjust preferences for handling potential spam.

The basic plan version of T-Mobile’s Scam Shield helps detect and block unwanted calls, protecting your device with regular updates and advanced network technology. You can also customize your block lists with the premium version of the app.

T-Mobile users can also stop robocalls for free by dialing #662# to turn on Scam Block features. Alternatively, you can also call 611 for assistance with these features.

AT&T spam call blocker

AT&T has the ActiveArmor app, which is free to install and helps block spam calls for their customers.

Here is how you can use AT&T ActiveArmor to block spam calls:

1. Download and install the AT&T ActiveArmor app.

2. Open the app and activate the fraud and spam call-blocking features using the toggle.

3. You can also customize settings to block, allow, or send potential spam calls to voicemail.

You can upgrade your AT&T plan to access advanced features such as the reverse number lookup and enhanced Caller ID features to help identify spam callers. AT&T customers can also block the most recent call by dialing *61.

Verizon spam call blocker

Verizon’s Call Filter is an app that helps block spam and unwanted calls and includes both free and paid options. Its free offering can help to manage call filtering and customize call-blocking preferences.

Here’s how to use Verizon’s Call Filter to stop spam callers:

1. Download and install the Call Filter app.

2. Open the app and log in with your Verizon account.

3. Use the toggles to turn on basic free spam protection, and set your preferences.

Verizon’s Residential Call Blocking for landlines can also help filter out robocalls and unwanted calls with spam detection and number blocking. To activate these services, log into your Verizon account or contact customer support.

UScellular spam call blocker

UScellular’s spam call blocker is called Call Guardian — the free version blocks high-risk calls and provides spam risk alerts, while the premium version adds features like detailed caller ID, customizable block lists, and the ability to block all nuisance calls.

Here are the steps to use UScellular’s Call Guardian:

1. Download and install Call Guardian.

2. Grant the necessary permissions (call logs and contact access) and verify your phone number.

3. Select the Free or Premium subscription to activate spam protection.

4. Customize blocking levels and manage your personal spam and block lists by adding known contacts.

8. Get a reliable spam call blocker tool

Third-party spam call blocker apps like Truecaller and Hiya use extensive databases and real-time reporting to detect and block spam calls. With features like detailed caller ID, custom block lists, and fraud detection, they offer users added protection against unwanted calls that might slip through built-in phone filters.

Here’s how to stop spam calls using a third-party app:

1. Download and install a trusted spam call blocker from the App Store or Google Play.

2. Register using your email or social media — you may need to verify your phone number.

3. Review and grant the appropriate app permissions (access to your contacts and call logs).

4. Go to the app’s settings and enable blocking features, such as spam call auto-blocking or filtering unknown callers. Customize your notification preferences.

Spam call blocker apps for mobile

Spam call blocker apps are designed to catch and stop spam calls. When choosing spam-blocking software, look for tools with anti-tracking features to stop advertisers from tracking your online activities.

• Hiya: Able to identify and block spam calls, including international numbers, Hiya can also help with real-time alerts, advanced blocking features, and detailed call reporting. It’s compatible with Android and iPhone.

• RoboKiller: Available for both Android and iOS, RoboKiller is a call blocker app that uses AI-driven Answer Bots to block spam and frustrate scammers from contacting your number again.

• Nomorobo: This robocall blocking tool offers advanced filtering and a CAPTCHA system for real human verification. Nomorobo is effective for both spam calls and texts and supports Android and iOS devices. It also works on VoIP landline phones.

• Truecaller: This privacy app operates from crowd-sourced reports to identify and filter spam. Truecaller is often rated for its robust caller ID and spam-blocking features, and is available for both Android and iOS.

Blocking spam calls using Truecaller for Android

To avoid falling for Trojan malware, research call blocker apps before you download them by checking the app reviews and searching the company online. Then use trusted security software like Avast Mobile Security to scan apps and alert you if any of them start behaving suspiciously.

Landline call blockers

You can find landline call blockers at electronics stores, online retailers, or via your phone service provider. Some devices come with built-in call-blocking software, others with an add-on service that requires a one-time purchase or an ongoing subscription fee.

Here are some third-party spam call blockers for landlines:

• CPR Call Blocker: The CPR Call Blocker blocks scam numbers preloaded to its database and also lets you add numbers from spam calls to your landline phone or VOIP network.

• Sentry Call Blockers: Sentry provides automatic call blocking and acts as a checkpoint that screens all incoming calls.

When choosing a call blocker for your landline, make sure it’s compatible with your phone system, easy to set up and use, and has adequate features to block robocalls, telemarketers, and spam calls.

Typically, to install a landline call blocker, you need to connect it to your phone line and activate the settings using the provided instructions.

9. Report spam calls to the FTC

The Federal Trade Commission (FTC) can investigate and take action against spam callers that overstep the mark — even those using unknown caller IDs. Reporting scams not only aids investigations but also helps the FTC identify patterns, improve fraud detection, and minimize future scams.

Here is how to report deceptive or suspicious spam callers to the FTC:

1. Visit the FTC's fraud report page and tap Report Now.

2. Fill out the report form with detailed information about the spam call or calls.

3. Tap Submit.

   

The FTC will acknowledge your report, likely with an automated email, but won’t provide an individual response. You can also report the spam number to the FTC by phone, at 1-877-FTC-HELP.

What is a spam call?

Spam calls are unsolicited phone calls made to large groups of people, often by telemarketers, robocallers, or scammers. While they can be a legitimate — albeit annoying — marketing technique, they’re also frequently used by scammers running phishing schemes or tech support scams, posing a risk to your privacy and security.

Types of spam calls

Here are some common types of spam calls to watch out for:

• Telemarketing: These are unwanted calls promoting products or services that often come from unknown or toll-free numbers. Be wary of high-pressure sales pitches or urgent calls about special deals.

• Robocalls: If you answer a call and hear a recording instead of a person, it’s a robocall. Robocalls often sell products illegally and are linked to scams.

• Autodial calls: These are calls made using automated dialing systems and typically have a noticeable delay before a live person starts speaking.

• Spoofed calls: This involves a scammer falsifying a caller ID to mask their true identity. The caller may pretend to be a legitimate business or trusted individual to steal your personal data for fraud.

• AI-powered spam calls: Scammers are harnessing the power of artificial intelligence to aid their voice cloning scams like family emergency schemes.

• IRS scam calls: These will typically have a spoof caller claim that you owe money or face legal action if you don’t pay immediately.

Why am I getting so many spam calls?

You’re likely getting spam calls because you unwittingly entered your number where you shouldn’t have, got caught in a social engineering scheme, or a company you shared your number with has suffered a data breach or sold your information.

Here are some of the most likely reasons why you could be receiving spam calls:

• You entered your phone number where you shouldn’t have like suspicious contests, trials on fake websites, or fraudulent apps.

• You engaged with a scammer online and inadvertently gave up your phone number.

• Your number was dialed randomly by scammers testing phone numbers to support their malicious activities.

• You picked up and engaged with a spam call in the past.

• Your number was added to a list of numbers that commonly pick up, respond to, or fall for scams.

• Scammers have purchased your number from data brokers.

• You were doxxed and your phone number was published on the dark web.

• You’ve fallen victim to a social engineering attack, such as phishing or vishing.

It’s safest to ignore calls from unknown numbers — important callers can leave a message, and you can find out who called you later. Answering spam calls increases the risk of receiving more in the future, and scam callers may attempt to hack your device. Instead, try to remove personal information from the internet to limit the number of spam callers finding your number.

Strengthen your online security to help avoid unwanted calls

Blocking spam calls is a great way to fight back against potential scammers — now fortify your entire phone against threats with powerful security that goes beyond call filtering.

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