Getting spam calls from numbers similar to my own

The telephone system has been designed so that a caller can replace their phone number with a fake, and some unscrupulous companies use this to change their number to appear to be local to the person they are calling. They aren't using specific numbers of people you know, just something picked at random. The thinking is that a person is more likely to pick up if they think it's a local call.

It is illegal to spoof your number with intent to defraud in the US and Canada, so what they are doing is probably against the law. You could report this to the phone company and they may look into it. Other than that you can't do much about this unless your phone company offers an add-on service to prevent it.

As GdD said, it's CallerID spoofing with the hope of tricking you into answering a 'local' call. I've had this happen where they used my own number as the Caller ID number! I answered because I thought there might have been a glitch in the matrix and that it was a legitimate caller, but no, it was spam (and yes, I should have known better.)

Their real goal may be to poison the spam blacklists. Consider services like NoMoRobo, which operate an effective CallerID blacklisting service to millions of people. By causing the addition of millions of legitimate numbers to the blacklist, the direction of the spammers could be to weaken blacklisting as a viable approach to dealing with spam.

Preventing CallerID spoofing will require a technical solution from the phone companies to end the problem. But they can't just shut if off, as there are still legitimate reasons for allowing substitute CallerID numbers. They are used by every company that runs their own Private Area Branch Exchange (PABX), so it's not like they can instantly stop supporting the feature without breaking a lot of their clients' phone systems. But the value of CallerID substitution to their clients is small, and the mountain of complaints is large and growing. They should just bite the bullet and end support for it.

Block it with CallControl by downloading it from the Android app store. Use the wild card option to block all numbers from that specific exchange.