iPhone has built-in tools to block most spam calls without installing anything extra

Your iPhone can filter spam calls in two ways: Filter Unknown Senders silences calls from numbers not in your contacts, and Call Filter uses Apple's database to identify and block known spam. Both are free and built into iOS. You turn them on in Settings, and they work in the background — you won't see or hear calls that get blocked, though a record stays in your Phone app if you need it later.

The difference matters. Filter Unknown Senders is aggressive: it sends any call from someone you don't know straight to voicemail. Call Filter is gentler — it still rings through, but labels the call as likely spam so you can decide whether to answer. Most people use both together.

Key Takeaways

  • Filter Unknown Senders silences all calls from numbers not in your contacts, while Call Filter labels suspected spam but still lets it ring.
  • Both features are free and built into iPhone; you turn them on in Settings under Phone, not in a separate app.
  • Blocked calls go to voicemail and appear in your call history, so you can retrieve them if a legitimate caller tries to reach you.
  • If you need more control, you can block individual numbers manually or use a carrier-based filter through your phone company.

Turn on Filter Unknown Senders for the strongest protection

Open Settings, then tap Phone. Scroll down to Call Filtering and toggle on Filter Unknown Senders. From that moment on, any call from a number you haven't saved in Contacts goes straight to voicemail. You won't hear your phone ring.

This works best if you answer calls from people you know and let voicemail catch the rest. The downside is real: a doctor's office calling with test results, a delivery driver, or a callback from a job interview will all land in voicemail if you haven't saved their number first. Check your voicemail regularly, especially if you're expecting important calls. You can always call back a legitimate number that left a message.

Use Call Filter to label spam while still seeing the call

In the same Phone settings, toggle on Call Filter. This doesn't block calls — it lets them ring through, but marks them as likely spam on your screen. You see the call coming in and can choose to answer or decline.

Call Filter uses Apple's spam database, which gets updated regularly. It catches a lot of robocalls and known scam numbers, but it's not perfect — some spam still gets through, and occasionally a real call gets mislabeled. The advantage is that you stay in control. If you see "Likely Spam" on your screen and you're not expecting a call, you can ignore it. If you do want to answer, you can.

Block individual numbers manually if you keep getting calls from the same source

If a particular number keeps calling, you can block it directly. Open the Phone app, find the number in your call history, tap the info icon (the small circle with an i), and scroll down to Block This Caller. That number will never reach you again.

You can also block a contact by opening Contacts, selecting the person, tapping the info icon, and choosing Block This Caller. Blocked numbers can still leave voicemail, but you won't see missed call notifications. If you change your mind, go to Settings > Phone > Blocked Contacts to unblock them.

Your carrier may offer its own spam filter

Verizon, AT&T, T-Mobile, and other carriers have their own spam-blocking services. Verizon Call Filter, AT&T Call Protect, and T-Mobile Scam Shield are free versions built into your service. Some carriers also offer paid versions with more features.

These work alongside Apple's tools — they don't conflict. A carrier filter can catch spam before it even reaches your phone, which is useful if Apple's database hasn't identified a number yet. Check your carrier's website or call their customer service to see what's available on your plan and how to turn it on.

What to do if spam calls keep getting through

If you're still getting a lot of spam despite using Filter Unknown Senders and Call Filter, the calls are probably coming from numbers you've already saved or from numbers the spam database hasn't caught yet. This is common with new scam campaigns.

Block the specific numbers as they come in. If you notice a pattern — calls from numbers that are almost the same, or calls at the same time of day — that's a sign of a spoofing campaign, where scammers use fake caller IDs. You can't stop spoofing entirely, but blocking the numbers you do see will reduce the volume. If the calls are threatening or harassing, contact your local police department and report the number to the Federal Trade Commission at reportfraud.ftc.gov.

Frequently Asked Questions

Will I miss important calls if I use Filter Unknown Senders?

Yes, if the caller doesn't have their number saved in your Contacts. Doctors, delivery services, and callback numbers from businesses will go to voicemail. Check your voicemail regularly and save important numbers as you go. If you're expecting a specific call, ask for the number beforehand and add it to your Contacts.

Can I use Filter Unknown Senders and Call Filter at the same time?

No — they work differently, so you choose one or the other. Filter Unknown Senders is stronger but blocks more legitimate calls. Call Filter is gentler and lets you decide on each call. Most people use Call Filter alone, or use Filter Unknown Senders if spam is severe.

What happens to blocked calls?

They go to voicemail and appear in your call history as missed calls. You can listen to voicemail or call the number back if it turns out to be legitimate. Blocked callers won't know they were blocked — the call just won't go through to you.

Does my carrier's spam filter work if I use Apple's tools?

Yes. Your carrier's filter and Apple's tools work together. The carrier filter catches spam before it reaches your phone, and Apple's tools catch what gets through. There's no conflict between them.

Can I block calls from a specific area code?

iPhone doesn't have a built-in way to block entire area codes. You can only block individual numbers or contacts. If you're getting calls from many numbers in the same area code, block them one at a time as they come in, or use your carrier's spam filter, which sometimes has area code blocking as an option.