It is possible to block calls from a specific area code on your telephone. If you have caller ID, you can just ignore the phone call and not pick it up. Thanks in part to newer technology, you can now block calls coming in from one area of the country. You can add a call screening device to your phone to block every unwanted call from any area code that you choose. This would block some collection calls, misdialed numbers, junk faxes or just annoying phone calls in general.
Determine the area code you want to block from your phone. You can find a listing of all the area codes at http://home-and-office-phone-depot.com/pages/area-code-search.htm. This list by Home and Office Phone Depot lists area codes, states and part of the state the area code applies to.
Order a phone call gateway system. Avinta Communications and Privacy Corps are third party companies that specialize in telephone services like call blocking and caller ID. Prices for a phone call gateway system vary by company.
Hook up the device to your telephone. Both systems work in a way where callers need a code to reach you. When calling your phone number, they will be greeted with a message where they will need to enter the code. If the code is entered correctly, your phone will actually ring and you have the choice of answering or not. If someone calling doesn't have your calling code, they won't be connected to you, but to an answering machine. You can call them back at your convenience. This will not only block certain area codes, but will block other unwanted callers as well.
You can change your secret phone code. You have the option of picking the four-digit number you want to use.
If you block an area code on your phone, be aware that you may block important phone calls from coming in.