How to Stop and Block Spam Calls on iPhone and Android

Tired of spam calls? You can stop most of them in a few minutes. Turn on your phone's built-in spam filter, block the numbers that keep calling, and switch on your carrier's free spam protection. This guide shows you how to stop and block spam calls on iPhone and Android step by step, when a caller ID and spam call blocker app helps, how to report spam calls in the US and UK, and what to do if you answer one.

How to block spam calls on iPhone

These steps are for iOS 26 and later. If your iPhone runs an older version, look for the note under each step.

1. Screen or silence unknown callers

Go to Settings > Apps > Phone, scroll to Screen Unknown Callers and pick one option:

• Ask Reason for Calling: your iPhone answers calls from unsaved numbers before it rings and asks the caller for their name and why they're calling. Then it rings and shows you the answer, so you can decide whether to pick up.
• Silence: calls from unsaved numbers don't ring. They go straight to voicemail and still show in your call list.
• Never: screening is off and every call rings as usual.

Save important numbers, like your doctor or your child's school, in Contacts so they always get through. Good to know: calls aren't screened while you're roaming, and screening turns off for 24 hours after you call emergency services (Apple: Manage unknown callers on iPhone). More on that in our guide to emergency calls on iPhone.

Older iOS: on iOS 18, go to Settings > Apps > Phone and turn on Silence Unknown Callers. On iOS 17 and earlier, it's under Settings > Phone.

2. Filter unknown and spam calls

1. Go to Settings > Apps > Phone and scroll to Call Filtering.
2. Turn on Spam. Calls your carrier flags as potential spam or fraud are silenced, sent to voicemail and moved to a separate Spam list.
3. Turn on Unknown Callers too if you want calls from unknown numbers moved out of your main call list.

To check these lists, open the Phone app, tap Calls (or Recents in the Classic layout), tap the filter button and choose Unknown Callers or Spam. If someone you know lands there, tap Mark as Known (Apple: Screen and block calls on iPhone).

Older iOS: the carrier spam filter is called Silence Junk Callers. You'll find it in Settings > Apps > Phone > Call Blocking & Identification on iOS 18, and it only works with certain carriers.

3. Block a number on iPhone

1. Open the Phone app and find the number in your call list.
2. Tap the Info button next to it, scroll down and tap Block Caller. For a saved contact, open the contact and tap Block Contact.
3. To undo it, go to Settings > Apps > Phone > Blocked Contacts, tap Edit and unblock the number.

Blocking works well for one caller who keeps trying. Spam callers often fake or change the number they show, so the filters above do most of the work.

4. Turn on call blocking and identification

Go to Settings > Apps > Phone > Call Blocking & Identification. Turn on Business Call Identification to see business names from Apple Business Connect or your carrier. If you install a caller ID app, it shows up here too, and you need to turn it on before it can label or block calls.

How to block spam calls on Android

The steps depend on your Phone app. Google Pixel phones and many other Android phones use Phone by Google. Samsung Galaxy phones use Samsung's own Phone app.

Phone by Google: turn on caller ID and filter spam calls

1. Open the Phone app and tap More options > Settings > Caller ID and spam (called Spam and Call Screen on some phones).
2. Turn on See caller ID & spam. It's on by default.
3. Turn on Filter spam calls. Suspected spam calls won't ring, but they stay in your call history and can still leave voicemail.

On phones with automatic Call Screen, you won't see "Filter spam calls" because spam blocking is part of Call Screen. Also know that when a number outside your contacts calls, your phone sends that number to Google to show a business name or a spam warning (Google: Use caller ID & spam protection).

Call Screen on Pixel and some Android phones

Call Screen answers for you, asks who's calling and why, and shows you a live transcript. With automatic screening, your phone hangs up on calls it detects as spam and only rings for the rest.

• Set it up: open the Phone app, tap More > Settings > Spam and Call Screen (or Call Screen), tap Call Screen and choose a protection level.
• Where it works: automatic screening is on Pixel phones in the US, UK, Canada, Australia and Ireland. Manual screening (you tap Screen call) works on Pixels in more countries and on selected Android phones in the US and Canada.
• Limits: it doesn't screen calls automatically while you're roaming, and Google advises against automatic screening if you use call forwarding (Google: Screen your calls).

Block a number or hidden callers

1. Open the Phone app and tap More > Call history.
2. Tap a call from the number and choose Block / report spam. Reporting it helps flag the number as spam.
3. To block hidden numbers, go to More > Settings > Blocked numbers and turn on Unknown. This only blocks private or unidentified numbers. Numbers that aren't in your contacts still ring (Google: Block or unblock a phone number).

Samsung Galaxy: Smart Call caller ID and spam protection

1. Open the Phone app, tap More options (three dots) and then Settings.
2. Tap Caller ID and spam protection, turn it on and agree to the terms.
3. Turn on Block spam and scam calls, then choose Block all spam and scam calls or Only block high-risk scam calls.

Samsung's Smart Call is provided by Hiya and may not be available on every carrier or model. To block one number, open Recents, tap the number, open the menu below it and tap Block. Under Settings > Block numbers you'll also find Block calls from unknown numbers. Be careful with it: it blocks every number that isn't saved in your contacts or identified by Smart Call, including deliveries and appointments. Galaxy phones with One UI 8.5 or later also have AI Scam Detection, which warns you during a call that looks like a scam (Samsung: Block spam calls with Smart Call).

Caller ID and spam call blocker apps

Apps like Truecaller, Hiya and RoboKiller check incoming numbers against their own spam lists, which are built partly from user reports. They can label or block calls your phone and carrier miss.

• On iPhone: install the app, then go to Settings > Apps > Phone > Call Blocking & Identification and turn it on.
• On Android: the app asks for permissions during setup. Some also ask to become your default phone or caller ID app.

Before you install one, check three things:

• Privacy: read what the app collects. Some ask for access to your contacts or call log.
• Cost: some have a free version, others need a subscription after a trial. Check the price in the App Store or Google Play.
• Do you need it? Try your phone's filter and your carrier's free protection first. Add an app only if spam still gets through.

Turn on your carrier's free spam call blocking (US)

The big US carriers label and block spam calls on their networks, and the basic version is free. Your iPhone's Spam filter also relies on these carrier labels.

• T-Mobile ScamShield: labels calls as "Scam Likely" and can block them with Scam Block. Turn it on in the T-Life app or by dialing #662# from your T-Mobile phone (T-Mobile ScamShield).
• Verizon Call Filter: free on standard monthly and prepaid plans with a compatible phone. It labels spam as "Potential Spam" and sends high-risk spam calls to voicemail. Manage it in the Verizon Protect app or in My Verizon (Verizon Call Filter FAQs).
• AT&T ActiveArmor: free with every AT&T wireless plan. The ActiveArmor app blocks fraud and spam calls or sends them to voicemail (AT&T ActiveArmor).

Each carrier also sells paid upgrades with extra features. No filter catches every spam call, and some can block a call you want, so check your spam list or voicemail now and then.

Join the Do Not Call list and report spam calls

US: National Do Not Call Registry and the FTC

• Register for free at donotcall.gov. You can add a home or mobile number. Most telemarketers should stop calling once your number has been on the list for 31 days.
• Know the limits: charities, political groups, debt collectors and surveys can still call. Scammers ignore the list, which is why call blocking matters more.
• Report unwanted calls: report sales calls (after those 31 days) and robocalls at donotcall.gov/report. The FTC uses these reports to spot illegal callers.
• Lost money or shared personal details? Report it at ReportFraud.ftc.gov.

UK: Telephone Preference Service (TPS) and 7726

• Register with the TPS for free at tpsonline.org.uk, or text "TPS" and your email address to 85095 from your mobile. It's against the law for sales callers from the UK or overseas to call numbers on the list.
• Still getting sales calls 28 days after you register? Report them to the TPS. The TPS doesn't stop scammers (Citizens Advice).
• Report scam calls and texts to 7726: copy the caller's number and send it in a text to 7726, or forward a scam text to 7726. It's free, and your mobile network uses it to investigate and block the number (Ofcom: 7726).
• Lost money? Contact your bank, then Report Fraud online or on 0300 123 2040 in England, Wales and Northern Ireland. In Scotland, contact Police Scotland (GOV.UK: Report a scam).

What to do if you answer a spam call

1. Hang up. Don't press any buttons, even to "be removed from the list" or to speak to someone. The FTC warns this will probably lead to more unwanted calls.
2. Don't share anything. Never give out codes, passwords, card details or personal information to someone who called you.
3. Don't trust the caller ID. Scammers can fake the number they show. If a caller says they're your bank, your carrier or a government office, hang up and call back on the number from their official website or your card.
4. Don't call back unknown numbers. In the UK, numbers starting with 070, 076, 084, 087, 090, 091 or 118 can cost a lot to call.
5. Block and report the number with the steps above.
6. If you paid or shared details, call your bank straight away and report it (ReportFraud.ftc.gov in the US, Report Fraud in the UK).

Habits that keep your number off spam lists

• Keep your number private. Don't post it on social media, public profiles or online forms you don't trust.
• Use a second number for sign-ups. In the US, Google Voice gives you a second number you can hand out instead of your main one. See our list of Wi-Fi calling apps for more options.
• Check app permissions. Don't give apps access to your contacts or call log unless they really need it.
• Clean up old accounts. Remove your number from sites and services you no longer use.
• Save the numbers you need. Filters let your contacts through, so add the people and places that call you.

Travelling? Keep spam calls away from your trip

Your spam protection can work less well abroad. iPhone doesn't screen calls while you're roaming, and Google's Call Screen doesn't screen calls automatically either.

A data-only travel eSIM keeps you online without giving spam callers anything to ring. It has no phone number, unlike a local prepaid SIM, so you call and message through apps like WhatsApp or FaceTime instead. Here's how to make calls with a data-only eSIM. Your home SIM stays in your phone, and you choose whether to keep that line on.

Need a number you can give to a hotel or a restaurant in Europe, without sharing your main one? Some Bouygues Telecom plans come with a French +33 number for calls and texts. See Europe eSIMs with a phone number.

Planning a trip? Check that your phone is eSIM compatible, then pick a plan for your destination.

Europe, Mexico and Canada plans shown · data-only eSIMs, no phone number · Find the eSIM for your destination

FAQs

How do I block spam calls on iPhone?

Go to Settings > Apps > Phone. Under Call Filtering, turn on Spam, then set Screen Unknown Callers to Ask Reason for Calling or Silence. To block one number, tap the Info button next to it in the Phone app and tap Block Caller.

How do I stop spam calls on iPhone for free, without an app?

Use the built-in tools: Call Screening or Silence for unknown callers, the Spam filter, and blocking. Then turn on your carrier's free spam protection, such as T-Mobile ScamShield, Verizon Call Filter or AT&T ActiveArmor. All of these are free.

How do I silence unknown callers?

On iOS 26 and later, go to Settings > Apps > Phone > Screen Unknown Callers and choose Silence. On iOS 18, turn on Silence Unknown Callers in the same menu. On a Samsung Galaxy, Block calls from unknown numbers in Settings > Block numbers does something similar, but it blocks those calls, so make sure it doesn't catch calls you need.

How do I block "Scam Likely" or "Potential Spam" calls?

These labels come from your carrier. On T-Mobile, turn on Scam Block in the T-Life app or dial #662#. On Verizon, make sure the spam filter is on in the Verizon Protect app or My Verizon. On iPhone, also turn on the Spam filter so flagged calls go to voicemail.

Can I block spam calls on Android without an app?

Yes. In Phone by Google, turn on See caller ID & spam and Filter spam calls, or use Call Screen on a Pixel. On a Samsung Galaxy, turn on Caller ID and spam protection and Block spam and scam calls.

Will blocking a number stop all spam calls?

No. Spam callers switch numbers and fake their caller ID, so a block list only stops the numbers you've added. Spam filters and carrier protection also catch numbers you've never seen before.

Does the Do Not Call list stop spam calls?

It stops most legal telemarketing calls after 31 days in the US, and the TPS does the same in the UK. Scammers ignore these lists, so you still need call blocking and spam filters.