The fastest way to block unknown texts on your phone

Most phones let you block unknown senders directly in your messaging app without installing anything extra. On iPhone, open a text from an unknown number, tap the sender's name at the top, then tap Block this Caller. On Android, open the message, tap the three dots in the top right, and select Block. The blocked sender's future texts will go to a separate folder or disappear entirely, depending on your phone model.

If you get texts from many different unknown numbers, your phone's built-in filters work faster than blocking each one individually. iPhone users can go to Settings > Messages > Filter Unknown Senders and turn it on — unknown texts then land in a separate tab you can ignore. Android phones vary by manufacturer, but most have a similar setting in the Messages app under Settings > Spam Protection or Block.

These built-in tools catch most spam without you having to do anything after you turn them on. They do not require a subscription or a separate app.

Key Takeaways

  • iPhone's Filter Unknown Senders and Android's Spam Protection settings automatically sort unknown texts into a separate folder so you do not see them.
  • You can block individual senders by opening their text and selecting Block, which prevents future messages from that number.
  • Carrier-level blocking through your phone company catches spam before it reaches your phone, and most carriers offer it free or for a small monthly fee.
  • Do not reply to unknown texts or click links in them, because responding confirms your number is active and leads to more spam.
  • If a text claims to verify your identity or asks for a password, it is a scam — your bank or service will never text you asking for login details.

Using your phone carrier's spam-blocking service

Your phone company — Verizon, AT&T, T-Mobile, or another carrier — can block spam texts before they reach your phone. These services work at the network level, which means they catch texts your phone's built-in filters might miss. Verizon offers Call Filter, AT&T offers Call Protect, and T-Mobile offers Scam Shield. Most carriers provide a basic version free and a premium version for around $3 to $5 per month.

To turn on your carrier's service, log into your account on the carrier's website or call their customer service number on the back of your bill. You can usually set up it in minutes. The premium versions add extra features like blocking calls and texts from numbers that look like scams, but the free version blocks known spam sources and lets you report new spam numbers.

Carrier blocking is worth using alongside your phone's built-in filters because they catch different types of spam. Your phone filters unknown senders; your carrier filters known spam sources and numbers that mimic legitimate businesses.

Why you should not reply to unknown texts

Replying to an unknown text — even to say "stop" or "remove me" — tells the sender your number is active and monitored. Scammers and spam operations use this information to sell your number to other spammers or to target you with more messages. A single reply can lead to a flood of texts over the following weeks.

The same applies to clicking links in unknown texts. Links in spam messages often lead to fake login pages designed to steal your password, or they trigger malware downloads. If you click a link and land on a page asking for your password, bank details, or Social Security number, close the page when ready and do not enter anything.

If a text claims to be from your bank, your email provider, or another service you use, go directly to that company's official website or app instead of clicking the link in the text. Type the web address yourself or open the app from your home screen. Legitimate companies never ask for passwords or account details over text.

Reporting spam texts to your carrier and the FTC

When you report a spam text to your carrier, you help them identify new spam sources and improve their filters. On most phones, you can forward a spam text to your carrier's spam-reporting number. For AT&T, forward to 7726 (SPAM). For Verizon, forward to 22622. For T-Mobile, forward to 7726. Check your carrier's website for the exact number if you are unsure.

You can also report spam texts to the Federal Trade Commission at ReportFraud.ftc.gov. The FTC does not investigate individual reports, but patterns in reports help them identify large-scale scams and take action against the people running them. Include the sender's number, the date and time you received the text, and what the message said.

Reporting takes a few minutes and helps protect other people from the same scammers. It also creates a record if you later discover the text was part of a larger fraud attempt.

Third-party apps for blocking texts

If your phone's built-in filters and your carrier's service are not catching enough spam, third-party apps like TrueCaller, RoboKiller, and Nomorobo offer additional blocking. These apps use large databases of known spam numbers and machine learning to identify new spam patterns. Most charge $3 to $10 per month for premium features, though they offer free versions with basic blocking.

Third-party apps work best as a second layer of protection after you have turned on your phone's built-in filters and your carrier's service. They are not necessary for most people — the free tools usually stop 80 to 90 percent of spam. Use them only if you are still getting many unknown texts after using the free options.

Before installing any app, check its reviews on your phone's app store and make sure it comes from a company with a clear privacy policy. Some spam-blocking apps have been caught selling user data, so read what permissions the app is asking for before you install it.

Protecting your number from getting on spam lists

Spammers buy phone numbers from data brokers, from companies that sell customer lists, or by randomly generating numbers and testing which ones are active. You cannot stop all of this, but you can reduce how often your number ends up on a spam list. Do not post your phone number on social media, public websites, or online forums. Do not enter your number into online forms unless you trust the company and understand why they need it.

If you have already received spam texts, your number is likely already on a list. Changing your number is an option if the spam is constant, but it is usually not necessary — blocking and filtering tools handle most spam without you having to change anything. If you do change your number, ask your carrier to port your old number to a spam-blocking service first, so texts to your old number get filtered instead of sitting in limbo.

Scammers also target numbers that appear in data breaches. If you have been notified of a breach at a company you use, monitor your texts for spam from that company's name or from numbers claiming to be related to the breach. These are usually scams trying to get you to click a malicious link or enter your password.

What to do if unknown texts are asking for money or personal information

Texts asking you to confirm your identity, update your payment method, or click a link to "verify your account" are almost always scams. Banks, email providers, and other services do not ask for passwords, Social Security numbers, or credit card details over text. If you receive a text like this, do not reply and do not click any links.

If the text claims to be from a company you actually use, contact that company directly using a phone number or website you find yourself — not a number or link from the text. Call your bank's customer service number on the back of your card, or log into your account through the official app or website. Ask them whether they sent the text. In almost all cases, they did not.

If you already clicked a link or entered information, change your password for that account when ready and monitor your account for unauthorized activity. If the text asked for your Social Security number or credit card details, contact your bank and the three credit bureaus (Equifax, Experian, and TransUnion) to report potential fraud.

Frequently Asked Questions

Can I block all texts from unknown numbers at once?

Yes. Turn on Filter Unknown Senders on iPhone or Spam Protection on Android, and unknown texts will go to a separate folder. You can also ask your carrier to block all texts from numbers not in your contacts, though this may block legitimate texts from businesses you do not have saved.

Will blocking someone stop them from seeing that I blocked them?

No. When you block a number, that person can still call or text you — the messages just will not reach you or notify you. They will not receive a message saying they are blocked. Blocking is silent on your end.

What if I block a number by mistake?

You can unblock it anytime. On iPhone, go to Settings > Messages > Blocked Contacts and swipe left on the number to unblock. On Android, open the Messages app, go to Settings > Blocked Numbers, and tap the X next to the number.

Do I need to pay for spam blocking?

No. Your phone's built-in filters and your carrier's free spam-blocking service stop most unknown texts. Premium apps and carrier upgrades are optional and only worth paying for if free tools are not catching enough spam.

Can scammers spoof a real company's number to make their text look legitimate?

Yes. Scammers can make a text appear to come from your bank, PayPal, Amazon, or another company you trust. Never click links or enter information based on a text alone. Always contact the company directly using a number or website you find yourself to verify the text is real.