After I moved states, I discovered a pretty effective anti-spam call heuristic. If the call is coming from the same area code as my phone number, it is most likely spam.
It seems spam callers assume most calls will likely be from a local number and so they initiate calls from the same area code as the target. However, since the area code in my local area is completely different from mine (since I moved), this tactic actually backfires and acts as a pretty good spam signal.
I used to think that was a dumb move on the part of the scammers, and probably would only be effective in a small town where most of the people you know have the same prefix… Then I realized that most of the successfully scammed victims probably live in those small towns.
This probably had some logic historically with landlines—a neighbor is calling. It’s an anti-pattern for cell phones in the “wrong” area code. Used to get this a lot. Rarely today.
It seems spam callers assume most calls will likely be from a local number and so they initiate calls from the same area code as the target. However, since the area code in my local area is completely different from mine (since I moved), this tactic actually backfires and acts as a pretty good spam signal.