I got eight spam calls in one Tuesday afternoon. Eight. One was about my car’s extended warranty (I do not own a car). One was “Amazon” calling about a suspicious purchase. One was a robocall in Mandarin. By the fifth call, I was answering with increasingly creative profanity, which did not help but felt good.

I looked into spam-blocking apps. Most of them want a monthly subscription — five to ten dollars — to block calls that I never asked for in the first place. Paying money to stop harassment felt wrong. So I found the free ways. They work about ninety percent as well.

iPhone: Silence Unknown Callers

1. Go to Settings → Phone → Silence Unknown Callers.
2. Toggle it on.

Any number that is not in your contacts, recent outgoing calls, or Siri suggestions goes straight to voicemail. Your phone will not ring. You will see a missed call notification. Legitimate callers — doctors, delivery drivers, people you actually need to hear from — will leave a voicemail.

I was worried I would miss something important. In two years, the only important call this blocked was from a mechanic telling me my car was ready. He left a voicemail. I called him back. Crisis averted.

Android: Multiple Free Options

• Google Phone app (Pixel and some others): Open the Phone app → three dots → Settings → Caller ID & spam → turn on “Filter spam calls.” Google’s database flags known spam numbers and either blocks them silently or shows a red warning screen.
• Samsung phones: Phone app → three dots → Settings → Caller ID and spam protection → toggle on.
• All Android: Settings → Sounds → Do Not Disturb → allow calls only from contacts. Same result as iPhone’s Silence Unknown Callers.

The Nuclear Option: Carrier-Level Blocking

All three major US carriers offer free spam-blocking. You just have to enable it:

• T-Mobile: Dial #662# to enable Scam Shield.
• Verizon: Download the free Call Filter app, or dial *662 to enable basic blocking.
• AT&T: Download the free ActiveArmor app, or enable “AT&T Call Protect” in your account settings.

These work at the network level — the call never even reaches your phone. It is the most effective option and costs nothing.

What About the National Do Not Call Registry

Add your number at donotcall.gov. It takes two minutes. It will not stop scammers — scammers do not care about laws — but it stops legitimate telemarketers. Fewer total calls means fewer to block. You have to renew every five years, which is absurd, but it is free and easy.

My spam calls dropped from daily to maybe once a week after combining Silence Unknown Callers with T-Mobile’s Scam Shield. I have not yelled at a robocaller in months. My blood pressure thanks me.