The fastest way to block robocalls depends on what phone you have

If you have an iPhone, turn on Silence Unknown Callers in Settings > Phone > Silence Unknown Callers. This sends any call from a number not in your contacts straight to voicemail. Android phones vary by manufacturer, but most have a Block Unknown or Spam Protection toggle in Settings > Apps > Phone > Permissions or Settings > Call Settings. Both approaches stop most robocalls without you having to do anything else.

If you want more control — blocking specific numbers instead of all unknowns — your phone's built-in call blocking works too. On iPhone, open the Phone app, find the number you want to block, tap the info icon, and select Block This Caller. On Android, long-press the number in your call log and tap Block Number. These blocked numbers will never ring through again.

Your phone carrier also offers robocall blocking at no extra cost. AT&T Call Protect, Verizon Call Filter, and T-Mobile Scam Shield all run on their network and catch robocalls before they reach your phone. These are turned on by default on most newer phones, though you may need to set up them in your carrier's app or online account.

Key Takeaways

  • Silencing unknown callers (iPhone) or enabling spam protection (Android) stops most robocalls without blocking people you know.
  • Your phone's built-in call blocking lets you manually block specific numbers that keep calling back.
  • Your carrier — AT&T, Verizon, T-Mobile, or another — offers free robocall filtering that works on their network before calls reach you.
  • Third-party apps like RoboKiller and Nomorobo add extra filtering, but the built-in tools handle the majority of robocalls for most people.

When to use your carrier's robocall filter instead of silencing unknown calls

Silencing unknown callers is the simplest option, but it means you will miss calls from real people — your doctor's office, a delivery driver, a job interviewer — if their number is not in your contacts. Your carrier's robocall filter lets legitimate calls through while blocking the spam, so you do not have to choose between missing real calls and hearing robocalls.

To turn on your carrier's filter, open their app or log into your online account. AT&T Call Protect is in the AT&T Mobile app under Security. Verizon Call Filter is in the My Verizon app under Settings > Call Settings. T-Mobile Scam Shield is in the T-Mobile app under Account > Call & Text Settings. Once you turn it on, it runs automatically in the background.

If you do not have the app, you can also call your carrier's customer service line and ask them to set up robocall blocking on your account. They can do it in a few minutes without any action on your part.

How third-party call blocking apps work and whether you need one

Apps like RoboKiller, Nomorobo, and Whoscall add another layer of filtering beyond what your phone and carrier already do. They use databases of known robocall numbers and machine learning to spot patterns that look like spam. Some also let you set custom rules — for example, blocking all calls from a certain area code or allowing calls only from your contacts.

Most people do not need a third-party app. Your phone's built-in tools and your carrier's filter catch 80 to 90 percent of robocalls for most users. Third-party apps are worth trying if you are still getting multiple robocalls a day after turning on your carrier's filter, or if you want features like call recording or a community blacklist of numbers other users have reported.

Be aware that some third-party apps ask for permission to access your contacts, call history, or location. Read the app's privacy policy before installing it. If an app asks for permissions that seem unrelated to call blocking — like access to your photos or location — that is a sign to skip it.

Why you should not answer or engage with robocalls

Answering a robocall, even to hang up, tells the caller that your number is active and monitored. They will add it to their list and call back more often. The same goes for pressing a number to be removed from their list — that is usually a scam to confirm your number works.

If you do answer by accident, hang up without saying anything. Do not press any buttons, do not say yes or no, and do not ask to be removed. Silence and a hang-up are the only responses that do not make things worse.

If a robocall is threatening, impersonating a government agency, or asking for money or personal information, you can report it to the Federal Trade Commission at ReportFraud.ftc.gov. The FTC uses these reports to pursue the worst offenders, though individual reports do not usually result in when ready action.

What to do if robocalls continue after blocking is turned on

If you are still getting multiple robocalls a day, your carrier's filter may not be set to the strictest level. Log back into your carrier's app and look for a setting called "Aggressive," "Maximum," or "Strict" filtering. Switching to a higher level will block more calls, though it may occasionally block legitimate calls too.

You can also add specific numbers to your phone's block list as they call. This is tedious if you get many robocalls, but it works for repeat offenders. On iPhone, go to Phone > Recents, tap the info icon next to the number, and select Block This Caller. On Android, long-press the number in your call log and tap Block Number.

If robocalls are coming from numbers that look like they are from your own area code or your own number, that is spoofing — the caller is faking the number that appears on your screen. Blocking individual spoofed numbers does not help because they will use a different fake number next time. In this case, make sure your carrier's filter is on its highest setting and consider a third-party app.

How to report robocalls to your carrier and the FTC

Your carrier wants to know about robocalls that get through their filter. Report them through your carrier's app or website. In AT&T Mobile, go to Security > Report Spam. In My Verizon, go to Call Settings > Report Spam. In T-Mobile, go to Call & Text Settings > Report Spam. These reports help your carrier improve their filter.

For scam robocalls — ones asking for money, threatening legal action, or impersonating a bank or government agency — report them to the Federal Trade Commission at ReportFraud.ftc.gov. You can also file a complaint with the Federal Communications Commission at fcc.gov/complaints if the calls are harassing or violate the Telephone Consumer Protection Act.

Reporting does not stop the calls to you when ready, but it creates a record that law enforcement can use to pursue the worst offenders. It also helps the FTC and FCC understand which scams are most common right now.

The difference between robocalls, spam calls, and scam calls

Robocalls are any calls made by an automated system rather than a person. They include legitimate calls — appointment reminders from your doctor, delivery notifications, school closures — and illegal ones like spam and scams.

Spam calls are robocalls trying to sell you something: credit cards, car warranties, home security systems. They are annoying but not usually dangerous. Your carrier's filter catches most of these.

Scam calls are robocalls trying to steal money or information. They might impersonate your bank, the IRS, a utility company, or a tech support service. These are the most harmful and the ones worth reporting. Your carrier's filter catches some, but not all, because scammers constantly change their tactics and phone numbers.

Frequently Asked Questions

Can I block all calls except those from my contacts?

Yes. On iPhone, go to Settings > Phone > Silence Unknown Callers and turn it on. On Android, the exact steps vary by phone, but look for Settings > Apps > Phone > Spam Protection or Settings > Call Settings > Block Unknown. This sends any call from a number not in your contacts to voicemail, though you can still see that they called.

Will blocking robocalls stop my doctor or delivery driver from reaching me?

If you use Silence Unknown Callers, yes — they will go to voicemail. If you use your carrier's robocall filter instead, no — it lets legitimate calls through while blocking spam. Your carrier's filter is the better choice if you need to receive calls from numbers not in your contacts.

Do I have to pay for robocall blocking?

No. Your phone's built-in call blocking is free, and your carrier's robocall filter is free. Some third-party apps charge a monthly fee, but most offer a free version that works well enough for casual users.

What should I do if a robocall is threatening or asking for money?

Hang up without answering any questions or pressing any buttons. Do not confirm your number is active. Then report it to the Federal Trade Commission at ReportFraud.ftc.gov. If the call impersonated a specific company or government agency, you can also report it directly to them.

Why do robocalls keep calling if I have blocking turned on?

Scammers use spoofing to fake different phone numbers each time, so blocking one number does not stop them from calling with a new fake number. Make sure your carrier's filter is set to its highest level. If robocalls continue, try a third-party app like RoboKiller or Nomorobo, which use databases and machine learning to catch spoofed calls your carrier's filter misses.