10 digit extension number

is there any reason you can’t use 10-digit dialing.
numbers that don’t match the internal extension list just send it to a trunk group.

What I’m I missing here?

10 digits isn’t an extension its a phone number. People who typically want this are trying to play phone company and actually want a sip router not a PBX. FreePBX is not a sip router. That out of the way there is NP reason you can’t have 10 digit extensions. It is just better not to use a hammer to put in screws

The reason why 10 digit dialing is “not necessarily a good thing” is that it is only a “phone number” in a subset of the world, specifically in NANP territory that only accept 10 digit dialing, the country code for NANP (US, and 6? “territories and outlying areas” such as Micronesia and Guam, Canada and 22 Caribbean countries) is 1 and over the years 11 digit dialing has been encouraged by the industry to normalize customer dialing behavior.

To complete a phone call, each piece of equipment needs to fully identify the final destination before dispatching it unequivocally, from the days of pulse dialing that is why NewYork’s AreaCode was originally 212 and Los Angeles was 213 (add Chicago,Dallas etc. and you will see the pattern), it was just quicker and more efficient on equipment use.

The most efficient way to accomplish that is using the concept of the “most significant digits dialed”, calls can only be processed one digit at a time, On a Centrex system (for the youngsters here, Centrex was the original Telco’s answer to hosted PBX’s in North America, where the switching equipment was on site and expensive trunking was only needed for external calls, Sounds familiar maybe? ), that usually meant that 4 digits would complete no matter what, because no extension started with 9, one dialed 9 to get “an outside line” (that legacy is still apparent in FreePBX by default) . Until the call can be routed without ambiguity then the equipment needs to continue capturing the digits, If there is ambiguity then conventionally you will need to wait for a “timeout” often 5 seconds of no dial “pulses”. So us “old farts” learned never to use extensions that started with 0,1, or even 9 in PBX systems, there are no area code that start with 0 or 1 that’s why there is an ‘N’ in the dialplan, (and these DID’s remain still a problem to “sell” by the telcos :slight_smile: ).

So to summarize

11 digit calling in NANP land is the most efficient plan, and in many places is fully E164 congruent without having to think. Most LEC’s are moving towards that plan.
if you want to use 10 digit dialing for external calls chose local extensions that don’t collide with your nearby and most used LD area codes to prevent “annoyance calls” caused by stumble-dialing, and wait 5 seconds for ALL internal calls to complete.

BUT if all external calls start with 1 and all International/operator calls start with 0 then it only takes a maximum of two digits to fully identify the route to chose. Personally I have found that the least confusing route to take is to educate your users to always use 1NXXNXXXXXX , which luckily where I work is now the norm, we have a dozen or so AreaCodes within a few dozen miles, never mind CellPhones only the really “dyed in the wool” old-timers expect 7 digits to get you where you want.

A corollary you might have run into is very few VSP’s will terminate 7 digit dialing, so you have already had to patch around the missing AreaCode, just extend your thinking to the country-code also.

And as a final word, E164 some would consider to be the modern arbiter of how a non-exclusive worldwide “phone number” should be considered, ref:-

I see very good responses to this question already, but I am still confused as to why you are even asking the question. What is making you not able to use 10 digit dialing? You can create an extension with 10 digits, and when you make a call from an extension… it will check the existing internal extensions, then if none match, it WILL try your outbound routes. Is there something wrong with your outbound routes possibly? I have a couple of legacy PBX’s in my network (inherited) that do have customers with ATA’s that have 10 digit extension numbers and the routing works just fine.

I think your thinking about did and extensions numbers

Sent from my HTC One™ S on T-Mobile. America’s First Nationwide 4G Network.

i’d stick to 7 digit max to avoid routing issues.

Even 7 digit extensions could cause issues with local exchanges…

The bottom line is, the “outside world” uses 10- and 11- (or more) digit dialing.

For example, you might say “I’m going to have 10 digit extensions starting with 708. 7081111111, 7081111112, 7081111113…”
Sounds fine, right?

Until you try to dial a chicago suburb (708 area code). Now, the phone system says “Hmmm… I don’t know if the user is wanting to dial an extension, or a phone number…”

Not only that, it’s difficult for your users. 4 digit extensions give you thousands of potential extension numbers, and people can remember 4 digit extensions.

I’ve found that the best practice for every install that I’ve done is to get your DIDs, and match your extensions to those. So if I have a DID that is 708-555-1212, and an extension that is 1212, it’s easy for the user to remember their “direct number”, because it corresponds with their extension. Similarly, if I know my boss’s extension is 1215, I know that his direct number is going to be 708-555-1215 (because it’s the same area code and prefix as MY did, so I only have to remember his extension).