How many area codes are "REALLY" needed

Now that we’re facing the first overlay in Chicago (backround-- the CHI area was suppose to have an overlay 630 but it was opposed so they divided up into 847 AND 630 to not have this - but we will wind up with it anyway)

What I read in a Tribune article was that it wasn’t until 2000 that ALL the phone numbers in 312 and 773 were actually used. The area code 312 was split into 312 and 773 around 1990.

(which in a way makes no sense as you can still get a 312 number so how can they all be used --but that is what the newspaper said)

Now I understand that because numbers are issued in blocks that we run out faster. But if they weren’t just how many WORKING numbers could you get out of an area code?

Obviously you can’t have any starting with 1 and you have to give up the 111.211…911 prefexes

I looked on a couple of area code sites and found lots of info but not this number.

I’m just going by the guidelines you suggested to get my answer, but here’s what I got…

No phone numbers start with 0 or 1. (At least I think none do…) So you have 8 x 10^6= 8,000,000 phone numbers. Also, discounting the numbers that start with 211, 311, … 911 means you have to subtract 8 x 10^4= 80,000 more numbers. Which leaves you with 7,920,000 possible numbers per area code.

But there are probably more phone numbers that you can’t get. Like ones that start with 666. So the number above may be even smaller.

Correct (in Canada and the U.S. anyway).

Almost correct. The 555 exchange number is also special. Many people believe these numbers are never assigned, which is false:

So they are sort of ‘in limbo’, leaving 7,910,000 usable numbers per area code.

That’s the actual number. Carmel Car & Limousine Services in Manhattan is 212-666-6666. (Thanks, reversephonedirectory.com!) In my own area code (306 - Saskatchewan), which is far from being used up, there is a 666 exchange in Maple Creek, with actual telephones assigned to it.