How-to guides

17 guides · every claim sourced to official documentation.

Short, factual answers to the questions behind most number lookups: where a number is from, whether a call can be trusted, and what actually reduces robocall volume.

How-to guides
GuideIn one line
How to find out where a phone number is from Use the area code and prefix to locate where a US number was issued — and understand why that is not always where the caller is.
How to report robocalls Where to file robocall complaints so they actually feed enforcement: FTC, FCC, and your carrier.
How to check if a number is toll-free Seven codes — 800, 833, 844, 855, 866, 877, 888 — are toll-free. Everything else is not, including lookalikes.
What is STIR/SHAKEN and does it stop spoofed calls? The caller-ID authentication framework US carriers must run, what it can and cannot do.
How to block unwanted calls Carrier tools, phone settings and call-blocking apps — layered defense against robocalls.
How to register on the Do Not Call list Free, permanent, takes two minutes — and what it realistically changes.
How to tell if a call is spoofed Signals that the number on your screen is not the real origin — and how to verify a caller properly.
How to report an IRS impersonation call The exact channels for tax-scam calls: TIGTA, the FTC, and [email protected].
How to verify a caller claiming to be your bank One rule covers it: hang up and call the number on your card. Everything else is detail.
What is an overlay area code? Why one place has several area codes, and what an overlay changes for dialing.
Why do local numbers keep calling me? Neighbor spoofing explained with the numbering mechanics that make it possible.
How to read a US phone number (NPA-NXX-XXXX) What each part of a ten-digit number encodes, and which digits are impossible.
How to look up which carrier holds a prefix Using public NANPA assignment records to find the code holder for any NPA-NXX.
What happens when an area code runs out of numbers? Exhaust forecasts, jeopardy status, and how relief overlays arrive.
How to stop spam texts Report to 7726, block, and never tap links — the smishing playbook.
Is calling an 855 number free? Yes — 855 is toll-free. What that means precisely, and the edge cases.
Can you get off robocall lists? What actually reduces call volume — and the 'removal' offers that increase it.