The best I’ve found is to simply reject all calls not in my contacts. Real callers leave a voicemail, which gets transcribed.

Doesn't work so well if you're on-call or running a business.

Those are usually generated, they call numbers in area code/exchange randomly, assuming you will pick up something that seems familiar. Jokes on them, I moved to another state, easy for me to tell.

Best thing I ever did for myself was to get a Google Voice number in an area code I've never lived in.

A lot of these fake calls rely on people assuming "local number = neighbor" kind of mentality which rarely comes into play these days as we're much more mobile than we used to be. Plus area code splits, separate area codes for cell vs landline services becoming increasingly common.

If my GV number were: AAA-BBB-CCCC

And my actual home area code is DDD-EEE-FFFF

Any and all numbers from AAA-BBB-xxxx can be ignored.

I never answer calls that come in on my cell carrier provided number, so that eliminates that issue. Silent ring, no forward to voicemail.

Anything left, about 95% of the time, tends to be legit.

With regional calling being a thing of the past and most cell plans being unlimited text and talk, it makes very little sense to keep a local number. Especially now as it's SOP for roboscammers to fake Caller ID and try to match the first 6 of your 10 digits.

Not natively, but there is an API that apps can use to do it for you. I use Mr. Number because it’s literally the first one I found and it’s worked good enough for me.

on iOS there is a lifesaving phone setting of sending unknown callers straight to voicemail.

I toyed with that for a while but I kept missing important work calls. I might have a look for an app later, but I have a feeling it might not exist...

Yeah. I tend not to pick up calls that are in the "Who would be calling me from Texas?" vein. But while it's annoying to have to look at my phone when it rings, I do get calls from locations that seem plausible and they usually are legit. I'm not really willing to make myself harder to reach for legitimate and even important reasons because of the occasional junk call.

I wonder if you can get a VoIP number from a different country (where good regulation means spam is less prevalent) and use that for work calls?

I'm almost 100% sure your employer wouldn't want to make an international call every time they wanted to contact you by phone.

Work uses slack/teams/Webex. One person sends me Signal. No one has ever used telephony, except I use it to call he dial in numbers because my phone audio is better than Bluetooth / virus agent laden laptop displaying ten videos of peoples homes thru vpn.