> Some of the places where cross-area code 7-digit was permitted, and
>> may still be, were local calls in the greater Kansas City area (816
>> in Missouri and 913 in Kansas)
U.S. phone companies ended "protected" prefixes several years ago. That was the arrangement near the edge of an area code that let you dial local calls with 7D into another area code, by reserving the prefix in both area codes.
Canada still had this arrangement until I think last year, notably in the Ottawa / Hull area which is partly in 613, partly in 819. They're also ending protected codes so people in Ottawa now have to dial all ten digits to Hull and vice versa.
R's,
John
[TELECOM Digest Editor's Note: And did you know that through the 1960's and into the 1970's, prefixes were not duplicated in adjacent area codes/states. For example, since Hammond/Whiting, IN (219 but exactly on the state line with Illinois and Chicago) since there was 219-931, 219-932, 219-933, 219-659 there were NOT any 931,932,933, 659 exchanges in area 312. I guess there was concern about possible confusion. I remember the first of those exchanges to get duplicated 'on the other side' was 659; 312-659 was intended for Cellular One in the earliest cell phone days of 1982-83. 219-659 on the other hand had been Whiting, IN since it was cut to dial in the 1960's. PAT]