The fastest way to block robocalls depends on your phone type

Most phones now have built-in robocall blocking that you turn on in Settings. On an iPhone, go to Settings > Phone > Call Blocking & Identification and toggle on "Silence Unknown Callers" — this sends calls from numbers not in your contacts straight to voicemail. On Android, open the Phone app, tap the three dots in the top right, go to Settings > Spam and Abuse, and turn on "Filter Unknown Calls" or "Block Unknown." These built-in tools stop most robocalls without you doing anything else.

If you want more control, you can also add specific numbers to your block list manually. On iPhone, open the contact or recent call, tap the info icon, scroll down, and tap "Block this Caller." On Android, long-press the number in your call log and select "Block number." These blocked numbers will never ring through — calls go straight to voicemail or are rejected silently.

Key Takeaways

  • Turn on "Silence Unknown Callers" on iPhone or "Filter Unknown Calls" on Android in your phone's Settings to stop most robocalls automatically.
  • You can manually block individual numbers by finding them in your call log or contacts and selecting the block option.
  • Your phone carrier (Verizon, AT&T, T-Mobile, etc.) offers free robocall blocking tools that work alongside your phone's built-in features.
  • Third-party apps like RoboKiller or Nomorobo add extra filtering but require you to route calls through them or give them permission to screen calls.
  • Do not answer calls from unknown numbers, return calls to suspected robocalls, or press buttons when prompted — these actions confirm your number is active.

How to use your carrier's robocall blocking service

Your phone company offers free robocall blocking that works before calls even reach your phone. Verizon offers Call Filter (free version blocks known spam), AT&T offers Call Protect (free version identifies suspected spam), and T-Mobile offers Scam Shield (free version blocks known scam numbers). These services sit between incoming calls and your phone, so they catch robocalls your phone's built-in filter might miss.

To turn on your carrier's service, call their customer service number (on your bill or the back of your card) and ask them to set up robocall blocking. Some carriers let you turn it on through their app or website instead. The free versions block numbers that are already flagged as robocalls in their database. Paid versions (usually $3 to $5 per month) add extra features like blocking calls from spoofed numbers or letting you set custom rules, but the free version stops most robocalls.

When to use a third-party robocall blocking app

Apps like RoboKiller, Nomorobo, and Truecaller add a second layer of filtering beyond what your phone and carrier already do. These apps use machine learning to spot patterns in robocalls — things like the timing of calls, the way numbers are spoofed, or the caller's behavior — and block them before they reach you. They also let you see a log of blocked calls and create custom block lists.

The trade-off is that these apps need permission to access your call log and contacts, and some require you to route all incoming calls through their system. Most offer a free version with basic blocking, and a paid version (usually $3 to $10 per month) with extra features like call recording or custom rules. If your phone's built-in filter and your carrier's service are already stopping most robocalls, a third-party app is not necessary. But if you still get several robocalls a week, adding one can help.

What to do if a robocall gets through

If a robocall reaches you despite your filters, do not answer or press any buttons. Robocalls often ask you to press 1 to speak to someone or press 2 to remove your number — pressing anything confirms your number is active and monitored by a human, which makes you a target for more calls. Hang up when ready and let it go to voicemail.

After you hang up, report the number to the Federal Trade Commission at ReportFraud.ftc.gov. You can also report it to your carrier — Verizon, AT&T, and T-Mobile all have options to report spam in their apps or by forwarding the call to a spam reporting number. Reporting helps your carrier and the FTC track which numbers are robocalls and add them to their block lists, which protects other people from the same calls.

How to block calls from spoofed numbers

Some robocalls use spoofing — they make their call appear to come from a local number, your bank, or a government agency. Your phone's built-in filter catches some spoofed calls, but not all. If you keep getting calls from what looks like your own number or a number you recognize, that is spoofing.

The best defense is not to trust the number on your screen. If someone claims to be from your bank or the IRS, hang up and call the official number on your statement or their website instead. Never give out personal information, passwords, or account numbers to an incoming caller, even if the number looks real. Your bank and the IRS will never call you asking for this information.

If spoofed calls are frequent, ask your carrier about paid robocall blocking options — AT&T Call Protect Premium and Verizon Call Filter Premium both have features that catch more spoofed calls than the free versions. You can also add the spoofed numbers to your block list manually, though new spoofed numbers will keep appearing.

Why some robocalls still get through

Robocalls are hard to stop completely because scammers change their tactics constantly. They use new numbers, spoof local area codes, and use technology that makes calls look legitimate. Your phone's filter and your carrier's service catch the robocalls they recognize, but new ones slip through before they are flagged.

The other reason some get through is that not all robocalls are illegal. Charities, political campaigns, and companies you have done business with can legally make robocalls if they have your consent or a prior relationship with you. Your filters may not block these calls because they are not spam — they are just unwanted. If you get repeated calls from a legitimate organization, you can ask them to remove your number from their list, or block the number yourself.

Frequently Asked Questions

Can I block all unknown callers?

Yes. On iPhone, turn on "Silence Unknown Callers" in Settings > Phone > Call Blocking & Identification. On Android, turn on "Filter Unknown Calls" in the Phone app settings. Unknown callers will go straight to voicemail, but you will not see a missed call notification. This works well if most of your calls come from people in your contacts.

Do I need to pay for robocall blocking?

No. Your phone's built-in filter and your carrier's free robocall blocking service stop most robocalls at no cost. Paid apps and carrier premium services add extra features, but they are not necessary for basic protection. Start with what your phone and carrier offer before paying for anything.

What if I block a number by accident?

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

Should I answer robocalls to get removed from their list?

No. Answering or pressing buttons confirms your number is active and monitored, which makes you a target for more calls. Hang up when ready. If you want to report the call, use ReportFraud.ftc.gov instead.

Can I report a robocall to the police?

Most robocalls are not worth police time unless they are threatening or part of a larger scam. Report them to the Federal Trade Commission at ReportFraud.ftc.gov and to your carrier instead. If a robocall involves a threat or extortion, then contact your local police department.