This matches my memory. 4-digit dialing in our town, and sometime late 70’s possibly very early 80’s it switched to 7-digit, and also stopped being long distance to call Saskatoon at the same time. Hmm. Then technically, prior to the switch, we didn’t dial 7 digits for anything. It would have been 4 or 8 (7 with a 1 or 0 prefix when calling long distance.)
This reminds me of my work desk phone when cell phones were new we still had seven digit dialing. Cell phones didn’t require the leading 1 and land lines did and people got confused.
My desk phone was something like 805-562-9122. The department of fish and game in Long Beach CA had numbers that all started with 562-912-2xxx. People calling from land lines in my area code would forget the 1 and therefore the phone would just recognize the first seven digits.
I got several calls a week from people looking for fishing licenses. I’d tell them that they forgot to dial 1 first and most people would chuckle and apologize. At least once a week someone would insist that I was mistaken and they definitely did dial the 1. Like, if you did then you wouldn’t have reached me dumb fuck.
The reason for he hierarchy of numbers is simply that the area code mostly designated the actual exchange that the low order numbers were handled by. Once you added a new exchange to an area, you needed to address it by its prefix code. And those calls went over tie lines between the exchanges, and these were limited in number. Hence why some telcos provided free calls in an area code - the calls didn’t ever leave the one exchange and didn’t use the precious tie lines.
Modern communications wipes al of this out. We just reticulate phone calls over the same data infrastructure that our Internet uses. Depending on your telco and where you live the calls may just use Internet Protocols anyway. For a while there was an adherence to ATM protocols on the links, but that has fallen away. So the idea of an exchange is obsolete, and it pretty much costs the telco the same to make a call to next door as to the other side of the country. Which leads to a desire for number portability, which slowly wipes out the notion of area codes. The next step should be a personal worldwide phone number. Which we almost have with mobile phones.
The issue with 9xx numbers noted above is odd. The x11 numbers were welded into the exchanges by design. Similarly for European phone systems, but they are the 11x numbers. (Curiously, apparently the reason the US systems use x11 whilst European systems use 11x is the way the numbers were effectively buffered in the mechanical autoselectors, With the US systems accumulating the number in reverse order to the European - so both use 11, but the service selection digit is at the other end of the number.) The US systems needed to see three digits before recognising that the number was a x11 number, and then would connect the call with only those numbers were dialled.
This might explain why the later special 9xx numbers fell though the cracks. They were selected to fit the pattern of 9xx, derived from 911. But this pattern isn’t special to the phone system. It was built with 911 being only one of a set of x11 special numbers. All the other 9xx numbers were free for use, and not special. Retrofitting a 9xx special number into the system is easy with a modern software defined system, but it breaks all the number allocation assumptions.
Back in the 70s I lived in a city of about 30,000. We had three exchanges, all of which started with 44x. If you were calling a number where their x was the same as yours, you could dial just the last four numbers. If x was different, you had to dial all seven numbers. The phone company installed new switching equipment in IIRC 1976 and we had to dial all seven numbers for any call.
OTOH, at the same time the non 44x phone numbers in the rest of the county stopped being toll calls, and we got touch-tone dialing, so it was a fair trade.
Reminder. In the US 10-digit dialing, e.g., 123-456-7890, the 123 is the area code, the 456 is the exchange or prefix, and 7890 is the local number.
In the town of less than 100 I lived in briefly, on Cape Breton Island in the mid 1970’s, there was a switchboard lady who put through your calls. She could often tell you if that person was in the house or not. She was also the postmistress.
Aged Phone Guy …
As has been amply and expertly explained, the answers are all over the literal map depending on which era (1930s, 1950s, 1970s, etc) and whether we’re talking a large urban area, a small city, a small town, or way up yonder in the holler.
If the OP can explain more about what they’re seeking we might be able to give more focused answers.
I grew up in Philly and we never (in my memory) had 4 digit dialing. Our number was GRA-3277 (the exchange was GRAnite) and my grandmother’s, around the corner was SHE(rwood)-xxxx. Later GRA was changed to GR2, and GR4 and GR6 were added. There was a TT(for nothing exchange) in NYC when I got there in 1962. Finally, they went to all numbers.
Here in Montreal, long distance calls have to be preceded by 1, so 11 digits are needed (that’s for calls in the North American zone that includes the Caribbean) but if you dial that 1 for a local call, you get an automatic message that you have to redial without the 1. Can’t those turds just put it through? I assume that 1 triggers the long distance billing mechanism, but couldn’t they program it to just ignore local numbers?
I had a girl friend whose parents had a summer home in the Poconos. The local phone service was owned and operated by one woman. There were only two circuits; one for the doctor and the second for the remaining 29 houses. Anyone could listen to any conversation. You had to wait for the line to be empty and then you pick up and the operator could connect you to any place in or outside of the tiny village. That was around 1955.
In the 1970s and early 80s I lived in a very rural area; I could dial with 5 numbers anyone in the same exchange which covered a large area, but very small population; the downside was (if I recall correctly) anyone else (even my school which was in town) was a long-distance call (or at least more expensive).
Funny thing is that in the suburbs where I lived before then, we had a party line, so the system I’m describing above was an upgrade.
When I was in college (also in the 70s) the town had the same thing, except I think there were three possible prefixes, so you could call using A-####, B-####, or C-####. I think the local phone directory even only listed numbers that way.
I lived for a little while in a small town in western Canada. The town had 4-digit dialing, then later expanded enough that they added another set of numbers. For the original, dial 4 -xxxx; for the others, 5 digits yxxxx.
I think it was the mid to late 80’s(?) I heard they hauled out all the mechanical switches, and replaced them with electronics. What used to be a huge 2-storey building was as a result almost empty except for a rack of electronics. This allowed all those fancy features I never had, like call forward, caller ID, blocking, built-in voicemail, etc.
Who remembers the days of home answering machines with those tiny cassettes?
Wow, sounds like you guys all grew up in Hooterville or something. I grew up about 20 miles outside Philly (Norristown) and like @Hari_Seldon always had seven digit dialing. In kindergarten (1965) we had to memorize our home phone number which was seven digits (I still remember the number). Also we were always supposed to carry a dime for a phone call in case of emergency.
I do remember a few businesses still used letters for the first two digits of the interchange - BR(oadway)9 was our local interchange, which I memorized as 279. Strictly a mnemonic device.
I had one of those into the 1990s (I may still have it somewhere in the house).
Those old mechanical switches were lots of fun!
My brother-in-law grew up in a small, small town and remembers his childhood phone number: 4. Like I said, SMALL town.
From 1961-1969 we lived in Croton-on-Hudson, 40 miles north of Manhattan, and had 4-digit dialing. Not exactly the sticks.
A decade+ later, in Ontario, we were getting too many wrong numbers to be plausible, and they were not close to our number (this was the era when you’d say “Sorry, you have a wrong number, what number were you trying to call?” and people would respond, so if they had been given the wrong number, they wouldn’t keep calling you.)
Eventually we figured it out. Our # was 742-4164. 885- was a valid local nxx (exchange); 884- was long distance. If someone in our nxx forgot to dial 1, or misdialed 884- instead of 885-, the (old, mechanical) switch would see 8, say ok; 8, ok; 4, NOT ok. It would then fail weirdly, dumping the next 4 digits back into the local switch including the 4, and ignoring the 7th digit. So 884-164x would ring our phone. I verified this using our modem line (remember those?). Shortly thereafter, they put in a DMS-100 and of course the fun stopped.
Sort of similarly, a cow-orker’s dad worked for Cincinatti Bell. They lived in a newish subdivision, where far less than half of the nxx was in use. But they wanted to plan for growth. So they put in ONE block of 10,000 numbers and set it up so the bottom half were in one nxx and the top half in another. But this meant that you could dial one nxx with a last four digits from the other and it would go through. In other words, if the two nxx were 345 and 987, and your number was 345-1234, you could dial 987-1234 and your phone would ring. Since this was undocumented and any such dial was a misdial, it was harmless, but made for a good party trick.
I effectively grew up in ‘Hooterville’, (a small town in Missouri with a population of approximately 2500) but I don’t recall when 4 or 5 digit numbers were ever used. My brain still retains several of the 7-digit numbers for friends and family from the 1960s-1970s. In the countryside, there were party lines with 3 or 4 households on the same line, but they upgraded to buried phone lines in the late 1970s and party lines ceased to exist in the area.
Aside: Around the time of that upgrade, the phone company’s repair guy managed to cut the new buried phones line in two, and I learned that his nickname was ‘Two-Wire’ because many of the locals, including my father, were of the opinion that he couldn’t fix or repair anything that had more than two wires. 
Free calls in-area meant that your exchange was not equipped to count calls. Only the out-of-area calls would be accounted, and historically that because the original multiple phone companies charged each other for transit and inbound calls.
In my system they did that. When people realized, they started dialing long-distance local numbers to get the itemized call records. The phone company fixed that. Either because they didn’t want to provide that information for free, or because there were complaints – I don’t know which.
Just to make it clear, back in the days with large area codes (sometimes encompassing whole states), free dialing (non “long distance” calls) was limited to a sub unit of the area code.
In our city, despite our local teleco not being a Bell and the city being in a Bell, we got free dialing to the city, but not to many other suburbs. All well within the same area code by a huge margin. (This resulted in relatives 20 miles away at the far side of the city being a free call while others 5 miles away in a nearby suburb weren’t.)
In short, a free dialing zone was usually smaller than an area code and larger than an exchange. Exceptions abound. The original Atlanta metroplex 404 area code was free dialing throughout despite being a seriously large area. Remote small towns might have had one exchange with everything outside that exchange being long distance.
And here is a song by Allen Sherman about the introduction of area codes.
Seemed appropriate. I took a class on this stuff back when I worked for Bell Labs, but it has all faded from my memory. My wife had 4 digit dialing in the late '70s in White River Junction, Vermont, also known as Peyton Place.
I’m probably at least as old as the average on this board, and I have no recollection of four-digit public dialing, probably because I’ve always lived in fairly big cities. I definitely do recall seven-digit dialing, before dialing area codes became mandatory. That was simply the result of running out of numbers; initially I think nearby suburbs would typically get their own area code even though calls from the inner city were still local, and eventually the city itself got several area codes in what I believe the telcos refer to as “overlays”.
The university where I worked for many years had a Centrex system, but I don’t remember if internal dialing was four-digit. With the “1” reserved for calling for an outside line, that would have meant a maximum of 9,000 numbers and probably less, which might not have been enough for a large campus.
A large company I used to work for had an interesting internal telephone network. Any company phone anywhere in the world could be reached from any other as a local seven-digit number. It was kinda like a global super-Centrex system. If calling from outside the company, you needed to know both the area code and the exchange. Only the last four digits were the same for the outside world.
Same here. L.A. was one of the first cities to have its area code split, in 1984, but seven-digit dialing continued to work for quite some time. I don’t remember when ten-digit dialing became necessary, but it wasn’t until a long time after the 213/818 split.
Fun fact: I had been carrying a mobile phone for at least a year or so before I learned that you don’t need to dial the “1” on a mobile.