Except for two areas in the United States, telephone calls require 10-digit dialing (and sometimes eleven—a 1 must be used as the first digit). And in areas that allow seven-digit dialing, it only works if the number you are calling from is in the same area code.
Then why do I see this?
Don’t parentheses imply that the area code is optional.
I see this format on Websites, business cards, stationery, signs, awnings, posters and the like. Even worse, when I travel to states other than New York, I see road signs with phone numbers that are only seven digits long. Try calling one of those from your cell phone.
Many of my customers insist that I use parentheses on their business cards and stationery.
Why don’t they get it?
Do they still have rotary phones as well?