So I've stumbled onto this by accident, but this works for me: Most spam calls that I get are using local number spoofing. I have an area code from where I gre

So I've stumbled onto this by accident, but this works for me: Most spam calls that I get are using local number spoofing. I have an area code from where I grew up, but live in a completely different state now. I can recognize the spam numbers immediately: if it's from the area code where I grew up, and it's not in my contacts, it's spam. Everything else I let through.