You can if you have an Androide cell phone. The App is called "tcallBlocking". There is a free version in which you can block up to 3 ph. numbers and then a full version that costs $2.00, allowing you to block unlimited numbers. I just bought the full version to use the wild card. By using the wildcard, you can block an entire area code by entering <206*>.
I have been getting the same calls from various different "206" area code numbers, so I found this App and it has been working for me.
Just got a call from this 206-496-0957. They left no message. I just added this number to my call blocker list. If you don't have this free app, get it now!