How to Block International Calls on Your Phone

If you don't have business or family abroad, the simplest way to eliminate ~80% of phone scams is to block international calls entirely. Here's how to do it on every platform.

On iPhone

iOS doesn't have a native "block all international" toggle, but you can get close:

1. Settings → Phone → Silence Unknown Callers. Enable this. Any call from a number not in your contacts goes straight to voicemail. This is the single most effective setting on iOS.
2. Settings → Focus → Do Not Disturb → People. Allow only contacts. Combine with Silence Unknown Callers for double protection.
3. For specific countries: open the Phone app → Recents → tap (i) next to the number → Block this Caller. You'll need to do this per number.

On Android (Google Phone app)

1. Open Phone app → tap menu (three dots) → Settings → Spam and Call Screen.
2. Enable See caller and spam ID.
3. Enable Filter spam calls. Suspected spam goes straight to voicemail.
4. For Pixel phones: enable Call Screen to have Google Assistant answer unknown calls.

Carrier-level blocking (US)

The most effective protection is at the carrier level, before the call even reaches your phone.

AT&T

• Free: AT&T ActiveArmor app (formerly Call Protect). Download from App Store / Play Store, sign in with your AT&T account, enable Spam Risk blocking.
• Free in-app: enable "Block Spam Risk Calls" automatically.

Verizon

• Free: Verizon Call Filter app, included with your plan.
• Settings → Block Calls → Enable High level filter. This blocks high-risk spam automatically.
• Premium ($3.99/mo) adds caller ID for unknown numbers.

T-Mobile

• Scam Shield is free and on by default.
• Dial #662# to enable Scam Block (blocks calls T-Mobile is highly confident are scams).
• Download the Scam Shield app for finer control.

Carrier-level blocking (UK)

• EE / Vodafone / O2 / Three: all support call blocking via carrier apps. EE has free Spam Shield. Vodafone offers Call Protect. Most UK carriers also support TPS (Telephone Preference Service) registration at tpsonline.org.uk.

Third-party apps

If your carrier's tools aren't enough:

• Truecaller (free + premium) - community-sourced spam database, very effective for international scam numbers.
• Hiya - partnered with AT&T and Samsung. Strong spam detection.
• Robokiller ($4/mo) - uses "answer bots" to waste scammers' time.

When blocking isn't enough: silence everything

If you're getting hammered with scam calls and nothing helps, the nuclear option is:

1. Enable Silence Unknown Callers (iOS) or Block all unknown callers (Android).
2. Enable carrier spam blocking at the strictest level.
3. Add legitimate businesses and doctors to your contacts so they can still reach you.

Yes, you'll miss the occasional legitimate call. But spam will drop by 95%+, and real callers can leave voicemail or text.

What about RCS / iMessage scams?

Blocking calls doesn't block SMS scams. For text scams, on iPhone go to Settings → Messages → Filter Unknown Senders. On Android, use Google Messages' built-in spam protection.

Bottom line

The single most effective action: enable Silence Unknown Callers (iPhone) or your carrier's automatic spam blocking. Real callers will leave voicemail. Scammers won't bother. You'll save hours of frustration and probably your bank account.