Guides
Background on the rules, tools, and tricks behind the numbers on this site. For active scam warnings from federal agencies, see our scam alerts page.

Which Area Codes Should You Be Wary Of?
Caribbean area codes that look domestic but aren't, and the one-ring callback scam that exploits them.

The Do Not Call Registry, Explained
What registering actually stops, what it doesn't, and how it fits alongside a site like this one.

The TCPA: Robocall Law in Plain English
The federal law behind most robocall lawsuits and complaint forms, explained without the legal jargon.

How to Block Spam Calls on iPhone and Android
Built-in call screening, carrier tools, and the tradeoffs of third-party call-blocking apps.

IRS and Tax Scam Calls: How They Work
The real IRS doesn't call demanding immediate payment or threaten arrest. How the scam script works and what to do when you get one.

Package Delivery Scam Calls and Texts
A fake unpaid customs fee or missed-delivery notice, and how to tell it apart from a real carrier notice.
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International Dialing & Country Calling Codes
Every country's calling code, and which ones are commonly spoofed by scam callers.