Phone extension forwards? or change for 2 digit extensions?


Hello all, after setting up all our extension, my manager does not want 4 digit extension, he wants our original ones as they are on everyone’s business cards…

Our format for extensions before was simply starting at 10 and went up, 11, 12,13 and so on…
The default now with UCM6208 is 1000, 1001, 1002, and so on. I know i can customize to a certain point , but the ucm62xx will not seem to take 2 digit extensions.
Ideas, suggestions?



You need change
PBX settings -> Genereal settings
User extension to other range (10-99)
you will also need change this to be inside user range but overlap themself.
Pick Extensions
Auto Provision Extensions

then you can create 10, 11 etc


I generally i use 3 digit, there are so many features in the system its going to take a lot of adjustments to get extension assignments to 2 digits.


Thanks for the quick reply…
Ya i figured that, damm, ok i will persuade the uppers to go with 4 digit with similar extensions, IE; ext 17 becomes 1017.

Maybe we can create stickers to put over existing business cards. :slight_smile:


You can keep the things on business cards as is and use an IVR to provide direct access to real extensions. Just make a menu item for each 2 digit extension to have it map to the correct 4 digit “real” extension.


Thats sounds cool how would i do that, are there any docs anywhere?



Well, make a new IVR and populate it with entries like:

  • 1 -> dial sales queue
  • 2 -> dial support queue
  • 12 - > dial extension 1012
  • 13 -> dial extension 1013
  • 14 - > dial extension 1014

Then make your IVR announcement be “dial your party’s extension at any time, or press 1 for sales, 2 for support.”


IVR in my Grandstream are 0-9 and *, i cant see how to do anything over 9, unless i am missing something.


Sorry - forgot UCM IVRs are not as flexible as FreePBX or straight Asterisk.


Actually you only need to create your extensions with 2-digits, the rest of the system can still use 4-digits (such as the ring groups and IVRs).

Simply “Check” the setting “Disable Extension Range” and then you can create your 2-digit extensions. The rest of the system stays as is.


First i do not recommend turning off extension range, you can mess a system by simple mistake.
Changing ext take some time but not much:
EXPORT all extension to csv, edit CSV and upload new digits.
Then you need reprogram phones and IVR/ring etc. It depend how big this is.

If you want fast map then use speed dial function :slight_smile: (for internal)


Thanks Cyfo for your reply…
For support reasons i prefer not to modify too much the original setup…
@Marcin does your solution only work for internal? As i would also need external callers to be able to reach the double digits too…

Thanks for all the help so far, I’m glad i purchased the Grandstream as I was told support was good…

Have a nice nice…


Not tested, you can try do it from IVR.


As cool is it would have been it does not work from IVR… :frowning: But thanks for the suggestion.


You can make it with dummy extension 12 and make forward on it to 1012.
CSV file is best for this.
You will need move call park if not used to extended numbers from xx to xxxx.

Then you can slowly upgrade all system.


So this is a horrible idea and I wish Grandstream would let you use any sequence of numbers for valid options on an IVR, but depending on how many extensions you need to map, you can build multiple IVRs as follows:

  • Assume your extensions are 1011-15 and 1021-25 (to make my life easy).
  • Assume you want people to be able to dial in and press “11” to get to 1011 (for instance)
  • Build one IVR (call it IVR-A) that has option 1 that goes to IVR-A1 and option 2 that goes to IVR-A2
  • Build IVR-A1 that has five options 1-5, that each goes to extension 1011, 1012, 1013, 1014, 1015
  • Build IVR-A2 that has five options 1-5, that each goes to extension 2011, 2012, 2013, 2014, 2015
  • Set your inbound route to be IVR-A and put a greeting on it. Do not put greetings on the other IVRs.

Now, when someone calls in they can go through your IVR “tree” to get to the final destination . You may need to play with timeouts a bit, but this will work most of the time.


Best is do correctly from start.
Also if there was Copy/move function for extension. I go there and move 1012 to 12 and UCM fix all groups etc.


Try this. Works perfectly for us.


Thanks i will give it a try