How to Block Scam Calls Automatically on iPhone & Android

Quick Answer: Block unknown calls automatically by enabling "Silence Unknown Callers" on iPhone (Settings > Phone) or "Filter spam calls" on Android (Phone app > Settings > Caller ID & spam). Both send all unknown calls to voicemail without ringing.

Why Automatic Blocking Matters

Manually blocking numbers doesn't work against scammers—they use new numbers constantly. Automatic filtering catches patterns and flags suspicious calls before they ring, saving you from spammy interruptions and scammy encounters.

iPhone: Block Unknown Calls Automatically

Option 1: Silence Unknown Callers

This sends all calls from numbers not in your contacts to voicemail silently, meaning you'll block scam calls from most scammers.

To enable on your iPhone:

1. Open Settings
2. Tap Phone
3. Scroll to Silence Unknown Callers
4. Toggle On

What happens: Unknown calls go straight to voicemail. You'll see them in your recent calls and can listen to messages.

Best for: People who rarely receive calls from unknown numbers and don't mind them going straight to voicemail.

Note: Calls from numbers you've recently called or texted will still ring, even if they are technically not in your contacts.

Option 2: Carrier Screening (Shows Labels)

If you want to see "Spam" or "Scam Likely" labels but still have calls ring:

1. Open Settings
2. Tap Phone
3. Tap Call Blocking & Identification
4. Enable any available carrier options

This varies by carrier. AT&T, Verizon, and T-Mobile all have options here.

Android: Block Scam Calls Automatically

Google Phone App (Pixel, many Android phones)

1. Open the Phone app
2. Tap the three-dot menu > Settings
3. Tap Caller ID & spam
4. Enable See caller and spam ID
5. Enable Filter spam calls to send spam to voicemail automatically

What happens: Suspected spam calls show warnings. With "Filter spam calls" enabled, high-confidence spam goes directly to voicemail.

Samsung Phones

1. Open the Phone app
2. Tap More (three dots) > Settings
3. Tap Caller ID and spam protection
4. Toggle on Caller ID and spam protection
5. Toggle on Block spam and scam calls for automatic blocking

Other Android Phones

Settings vary by manufacturer. Look for:

• "Caller ID and spam" in Phone settings
• "Block" or "Spam protection" options
• Download the Google Phone app for consistent features

Where These Features Falls Short

Spoofing Known Contacts

Caller ID cannot be fully trusted. Using device-based unknown caller silencing can provide a false sense of security around known calls. In family emergency scams, for example, callers may use spoof a known contact number and this will not be detected by any of the controls above on devices even when paired with blocking tools provided by your carrier. Learn more about how Caller ID spoofing works.

Important Unknown Callers

At Savi, we spend a lot of time thinking not just about how to block malicious calls, but also about how to surface the unknown, but wanted (and potentially important) calls. This may be a call from your kid's school, a delivery app, or a ride-share service. As your voicemail gets crowded with so many calls being silenced, it's easy to lose track of these important calls as well.

If you are actively interviewing for a job, trying to schedule a new vendor or waiting for results from a doctor you may want to either turn this feature off or be more vigilant about how you review/check your voicemails to ensure nothing timely is missed.

Balancing Your Tradeoffs

We recommend taking advantage of these device-based features to block scam calls particularly for young or elderly people who typically have a smaller circle of regularly, trusted contacts. Implementation for them and others may require some other changes in behavior or additional products in order to ensure you have the right balance of quieting the chaos and surfacing the most important calls in your life.

Tips for Best Results

• Layer protections: Use phone settings + carrier service + another scam protection app like Savi
• Check voicemail: Legitimate callers leave messages
• Save important numbers: Add doctors, schools, etc. to contacts
• Report spam: Helps improve databases for everyone

FAQs

Will I miss important calls if I block scam calls on my device?

Unknown calls go to voicemail, not blocked entirely. Check voicemail regularly.

What if a legitimate caller gets blocked?

They can leave voicemail. Add their number to contacts for future calls.

Do I need paid apps?

Free phone settings and carrier services work well for most people. Paid apps offer extra features.

Does this stop all scam calls?

It significantly reduces them. No solution is 100% effective.