The fastest way depends on your phone type
Most phones let you block unknown numbers directly in the Messages app or through your carrier's filtering service. On iPhone, you can turn on Filter Unknown Senders in Settings > Messages, which moves texts from people not in your contacts to a separate tab. On Android, Google Messages (the default texting app on most newer phones) has a spam filter you can enable in settings, and Samsung phones include a native spam filter in their Messages app.
If your phone's built-in filter is not strong enough, your carrier — Verizon, AT&T, T-Mobile, or another provider — offers a separate blocking service. These services catch more spam because they filter at the network level before texts even reach your phone. Each carrier names theirs differently: Verizon Call Filter, AT&T Call Protect, T-Mobile Scam Shield. Some tiers are free; others cost a few dollars per month.
Key Takeaways
- iPhone users can enable Filter Unknown Senders in Settings > Messages to move unknown texts to a separate tab without deleting them.
- Android users should turn on spam filtering in Google Messages or their phone's native Messages app, both of which block most common spam automatically.
- Your phone carrier offers a separate blocking service (Verizon Call Filter, AT&T Call Protect, T-Mobile Scam Shield) that catches spam before it reaches your phone.
- You can also block individual numbers manually by opening a text, tapping the sender's number, and selecting Block Contact or Block This Caller.
How to block individual numbers on iPhone
Open the text message from the number you want to block. Tap the sender's phone number or name at the top of the conversation. A menu will appear with options including Block This Caller. Tap it, then confirm. That number will no longer be able to text you, and any future messages from it will be deleted automatically.
If you have already deleted the message, you can still block the number. Go to Settings > Messages > Blocked Contacts and tap Add New. Type or paste the phone number you want to block. The number will be blocked immediately.
How to block individual numbers on Android
Open the text message from the number you want to block. Tap the three dots (menu icon) at the top right of the conversation. Select Block or Block Number. Confirm the block. Messages from that number will stop appearing in your inbox.
If you use Google Messages, you can also block a number by opening the conversation, tapping the three dots, and selecting Block & Report Spam. This sends feedback to Google about the sender, which helps improve spam detection for all users. On Samsung phones, the process is similar: open the message, tap More, then Block.
Using your carrier's spam filter service
Verizon Call Filter is available free with a basic tier that blocks known spam. The premium version ($3.99 per month) adds custom blocking lists and caller ID for unknown numbers. You can turn it on in the Verizon app or by texting a code to activate it.
AT&T Call Protect offers a free version that blocks known spam and scams. The premium tier ($4.99 per month) adds the ability to block calls and texts by category — like political calls or telemarketers — and shows you who is calling before you answer. Enable it in the AT&T mobile app.
T-Mobile Scam Shield is free for all T-Mobile customers and blocks suspected spam automatically. You can adjust filtering levels in the T-Mobile app: Standard blocks high-confidence spam, Aggressive blocks more borderline cases, and Off disables the filter. There is no paid upgrade.
Turning on built-in spam filters
On iPhone, go to Settings > Messages and toggle on Filter Unknown Senders. This does not delete unknown texts — it moves them to a separate Unknown Senders tab in your Messages app. You can still read them if you need to, but they will not clutter your main inbox. This setting works on iPhone 11 and newer.
On Android with Google Messages, open the app and tap your profile icon in the top left. Go to Settings > Spam and abuse and toggle on Block suspected spam. Google Messages will then filter incoming texts and move suspected spam to a Spam folder. You can review blocked messages there if needed.
On Samsung phones, open the Messages app, tap the three dots, go to Settings > Spam, and toggle on Spam Filter. You can also set it to block messages from unknown senders only, which is less aggressive than blocking all suspected spam.
What to do if blocking is not enough
If you are getting a high volume of texts from different numbers, blocking them one at a time will not solve the problem. In that case, contact your carrier and ask about their spam-blocking service. Most carriers can enable their network-level filter within minutes, and it will catch spam before it reaches your phone.
If you are receiving threatening or harassing messages, save them as evidence and report them to your local police department or the FBI's Internet Crime Complaint Center. Do not respond to the messages, as that can confirm your number is active and lead to more spam.
If the texts are coming from a specific sender you recognize — like a business or service — you can often unsubscribe by replying STOP. This works for legitimate marketing texts. Scam texts usually ignore STOP replies, so do not waste time on those.
Frequently Asked Questions
Will the sender know I blocked them?
No. When you block a number, the sender will not receive a notification. Their texts will simply fail to deliver, and they may see a delivery error after a delay. There is no way for them to know for certain that you blocked them rather than having a technical issue.
Can I unblock a number after blocking it?
Yes. On iPhone, go to Settings > Messages > Blocked Contacts and swipe left on the number you want to unblock, then tap Unblock. On Android, open the Messages app, tap the three dots, go to Settings > Blocked Numbers, and tap the X next to the number you want to unblock.
Do I need to pay for spam filtering?
No. Your phone's built-in filter (Filter Unknown Senders on iPhone, spam filter in Google Messages or Samsung Messages) is free and catches most common spam. Your carrier also offers a free basic tier. Paid options from carriers add extra features like custom blocking lists, but they are not necessary for most people.
What if I block a number by mistake?
You can unblock it anytime through your phone's settings. On iPhone, go to Settings > Messages > Blocked Contacts. On Android, open Messages, tap the menu, go to Settings > Blocked Numbers. Find the number and unblock it. The person will then be able to text you again.
Will blocking stop robocalls too, or just texts?
Blocking a number stops both calls and texts from that number on most phones. However, robocalls often come from spoofed numbers that change with each call, so blocking one number will not stop the calls. For robocalls, use your carrier's call-filtering service, which blocks them at the network level before they reach your phone.