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Avast Academy Security Other Threats Spam Text Messages (SMS) — How to Stop or Block Spam Texts

Spam Text Messages (SMS) — How to Stop or Block Spam Texts

Getting text messages from random numbers is disturbing, to say the least. But spam isn’t just annoying, it can also be a dangerous vehicle for malware. Keep reading to learn how to block texts and stop spam and other scam messages with our guide. Then get strong security software like Avast One to defend against spam, malware, and other online threats.

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What is a spam message?

A spam message is any kind of unwanted or unsolicited communication, often sent in bulk over the internet or through an electronic messaging service. On mobile, unwanted text messages usually come from unknown numbers or as robotexts sent by auto-dialers. Spam texts often promote a product or service.

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    Spammers don’t just use SMS messages. Spam can be sent in other forms, too, including phone calls from spam phone numbers, not to mention all the spam emails that inundate our inboxes.

    Most spam messages are relatively harmless, and filtering out spam is usually simple. But while most spam messages don’t pack computer viruses or other malware, some spammers may be phishing to harvest your personal data.

    How to stop spam text messages

    If you’re wondering how to block texts, there are a number of quick and easy steps you can take to stop getting messages from a specific number and reduce your overall vulnerability to spammers and the online scams they perpetuate.

    There are a range of built-in and third-party apps for filtering and blocking spam texts. And there are various organizations dedicated to investigating unlawful spamming and spoofing to which you can report spam texts and other potentially dangerous messages.

    Don’t respond

    No matter how annoying it is to receive text messages from random numbers, do not respond to them. In fact, that’s one of the worst things you can do, because it lets the spammers know that your cell phone number is active, and you could invite a barrage of more robotexts and other nuisance messages.

    Block numbers

    A simple way to keep scam text messages out of your inbox is to block spam numbers on your phone. This works on both iPhone and Android devices, and it prevents messages or calls from the blocked number from reaching you. Note that spammers may be able to bypass the block if they spoof someone else’s phone number.

    Report spam messages to your mobile network provider

    Scammers may be getting smarter, but mobile service providers are also getting better at identifying and shutting down spam phone numbers. Reporting suspicious or spam messages to your carrier helps protect yourself and others by preventing similar texting scams in the future. AT&T, Verizon, or T-Mobile customers can do this by simply forwarding the spam message to 7726.

    You can also report a suspicious phone number and lodge a complaint with the relevant authorities in your jurisdiction. In the US, unwanted texts and internet scams can be reported to the Federal Trade Commission via the National Do Not Call Registry. You can also add your number to their Do Not Text list, which bans spammers and telemarketers from targeting you.

    Use spam-blocking apps

    For an extra layer of spam security, use an app to proactively block text messages from scammers and spam phone numbers. These apps draw upon enormous databases that are constantly updated to automatically block text scams and spam messages.

    Best text blocking apps for Android

    The best text blockers for Android don’t just stop spam text messages. They also include features like call silencing and spam recognition that can alert you to possible scams. For extra protection against the spam nuisance, use an ad blocker for Android as well.

    Here are three of the best spam-blocking Android apps:

    • Calls Blacklist

      A complete call and SMS message blocking app, Calls Blacklist lets you block calls and text messages from both unknown and private numbers. You can also eliminate disturbances by blocking call notifications completely.

      Calls Blacklist is lightweight and completely customizable — you can block numbers with the same first digits and adjust other settings. You can also create a custom schedule to lock your phone whenever you want.

    • Key Messages

      Key Messages is an AI-driven text message blocker for Android that automatically blocks spam messages from unknown senders.

      It’s fully MMS-compatible, letting you send multimedia content easily. You can block SMS messages based on categories, and you can back up your data to your Google Drive account.

    • Call Control

      A comprehensive SMS blocker for Android, Call Control automatically recognizes and blocks spam calls and spam SMS messages.

      It has a built-in incognito mode that lets you hide incoming calls and messages, and its smart screening feature automatically denies all confirmed and probable spam contacts. Plus, you can create personalized blacklists.

    Best text blocking apps for iPhone

    For an extra layer of protection on iOS, get a text blocking app for your iPhone. Effective at stopping pretty much any spam, these top iOS text and call blockers get more powerful with each spam text report. Try an ad blocker for iOS to further protect against annoying disruptions on your phone.

    • Hiya

      A feature-rich call and SMS blocker app for iPhone, Hiya identifies spam calls, including robocalls and telemarketers, and blocks them automatically.

      You can easily view your blocked numbers and block spoofed spam calls by location (area code and prefix). Plus, its reverse phone lookup option helps you connect names to unsaved numbers.

    • TrueCaller

      One of the largest and most-popular spam-blocking apps, TrueCaller has a 100% free subscription tier, while systematically keeping spam texts at bay.

      It includes a spam-blocker and a caller ID, and it can automatically identify spam, robocalls, and other fraudulent communications before you answer them. Plus, its centralized database will confirm the identity of any spam caller based on the experience of other people on its network.

    • VeroSMS

      A dedicated SMS filter that puts your privacy first, VeroSMS lets you block texts by keyword or with region-based crowdsourcing data.

      VeroSMS doesn’t have access to your texts, and none of your data is sent to its servers. You can customize your contact list, banning outside callers while preventing verified contacts from being blocked.

    • SMS Shield

      A machine learning spam filtering app, SMS Shield works online and off to find and filter junk messages with high efficiency.

      Its manual control options let you block specific SMS contacts based on keywords, while its AI engine easily identifies new and recycled spam. It also features a frequent traveler mode so you can block border-crossing SMS messages.

    Don’t click on links in messages you receive

    Never click on any link in a text message or email unless it comes from a trusted source. Spam text messages are a classic vehicle for phishing scams that try to coax you into clicking links that can lead to pharming websites that steal your data or inject adware or other malware into your device.

    Protect your personal info

    Legitimate companies won’t ask for sensitive personal information such as your address, account passwords, or government identification numbers — especially not via SMS. Keep your personal data private or you risk becoming a victim of identity theft.

    If you are asked to hand over personal data, report the spam text message immediately and take steps to block unwanted messages from anyone or any number sniffing around for your personal details.

    Review your mobile bill regularly

    Some spam advertising campaigns and other mobile scams force your cell phone to call or text premium numbers, thereby running up your bill. Review your mobile statements and look for any unusually high charges, unexpected data usage, or anything unusual.

    Use your phone’s built-in spam-blocking features

    Check your phone’s security settings and use any built-in privacy features like call blocking, caller ID, spam filters, and any other anti-spam controls to help block unwanted text messages, spear phishing attempts, or other scams.

    How to block spam texts on Android

    When you see a spam text on your Android device, your immediate response should be to block the spam message. Here’s how to block unwanted texts on your Android phone:

    1. Open your messaging app and find the text you want to block. Then, tap the three-dot icon in the top-right corner of the screen.

      Select the three-dot icon from the message thread you'd like to block.

    2. Then, tap the Block number option (or select Block contact) and confirm.

      Select the "block" number option and confirm your choice in the pop-up box.

    Note that call and text blocking may vary depending on your Android device. And if you use a different Android calling or messaging app, the process might be slightly different.

    How to block spam texts on iPhone

    If you’re getting iPhone spam text messages, you can block them easily and make yourself less susceptible to future attacks.

    Block spam texts from the Messaging App

    Here’s a step-by-step guide for blocking spam messages and unwanted texts on your iPhone:

    1. Open the spam text message.

    2. Tap the name of the sender, then tap the Info icon at the top of the screen.

      Open the spam thread, then select "info" at the top of the screen.

    3. Select Block this Caller at the bottom of the screen.

      From the contact info page, scroll to the bottom and select "block this caller."

    Filter and block spam texts on iPhone automatically

    Your iPhone can also filter out spam text messages on its own. Here’s how to block spam texts automatically:

    1. Go to your iPhone’s Settings and tap Messages.

      Head to the "messages" section of your iPhone's "General Settings."

    2. In the Message Filtering section, toggle the button for Filter Unknown Senders to on. Now any messages you receive from unknown numbers will be collected in a separate list.

      From "general settings," select "messages" and turn on the "filter unknown senders" setting.

    What is a phishing text message?

    Text message phishing is a scam that tries to fool you into providing sensitive information, such as usernames, passwords, or credit card info. Compared to typical spam that may only advertise an offer or service, phishing texts usually aim to steal your personal data and use it against you.

    Phishing attacks may also try to get you to install malicious software. Antivirus software can help prevent phishing attacks and keep your device and data safe.

    What are robotexts and how to stop them?

    Robotexts are automated messages (robot messages) used by spammers to mass-send unwanted advertisements and other junk. Thankfully, you can block robotexts sent by bots in the same way that you can block other kinds of spam.

    As always, don’t interact with the text except to block the number to prevent it from sending you more spam in the future. Then, report the spam text and spam phone number to alert your mobile carrier to the problem. Finally, use your phone’s built-in filtering and blocking features to shield yourself from all kinds of spam.

    What is SMS bombing and how to stop it?

    SMS bombing happens when people flood the inbox of a particular number with a torrent of spam messages from apparently different numbers. Certan apps and websites specialize in SMS bombing, which can be difficult to stop given the sheer volume of spam texts.

    Often done as a prank, SMS bombing can also constitute a cybercime, especially if it’s used as a cyberbulling technique. Built-in spam filters and third-party spam blockers can help protect against SMS bombing. And you can also sign up to Do Not Text lists to help prevent SMS bombing attacks on your number.

    Add extra protection with Avast One

    Some spam may be harmless, but spam links and unsolicited messages can contain malware that can do real damage to your device. For an extra layer of protection against threats lurking in spam messages, Avast One is your solution.

    Featuring AI-powered threat-detection technology, Avast One offers real-time protection against spam, malware, and other online threats, keeping your sensitive information — and your system — safe. Available on both Android and iOS, it’s never been easier to stay protected against spam.

    Block spam and get real-time protection with Avast One


    Block malicious, spammy websites with Avast One

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    Anna Faller