Redirect outgoing premium rate numbers to standard equivalent

[slapster]

In the UK, we often have to dial companies who use premium rate non-geographic numbers. This irks me, when we pay around 25x as much to call them. So I have blocked some numbers with particular prefixes. I would like to map specific non-geographic numbers to their geographic equivalents, so our users experience a seamless call and we don't pay silly money for them.

I have tried using an outgoing rule putting the full non-geographic number in "Calls to numbers starting with prefix", then stripping all the digits and prepending with the replacement number. But there are 11 digits, and I can strip a maximum of 9, so that won't work.

Is there a better way of achieving this?

Many thanks!

 

[ChrisC_3CX]

The fact that you can only strip 9 digits may indeed mean that this is not possible to do. I take it the two numbers (geographic and non) do not have common digits at the end?

 

[slapster]

Hi Chris, yes that is right. It's very common in the UK to have completely different non-geographic numbers aliased to standard numbers. Mostly they are benign (either free 0800 or local rate 0345) but some use 0845 and other similar ones which cost a premium and earn them rebates. This explains the situation https://www.saynoto0870.com/

It would be quite helpful to have a redirect table in 3CX so that as admin, I can get premium numbers redirected to standard numbers with a higher priority than the general block for the premium prefix.

 

[ChrisC_3CX]

In that case there's not much that can be done through 3CX I'm afraid. I have to say though, this does sound like something that the SIP Provider may be able to take care of so I think your best bet would be to reach out to them to see if this is possible to configure on their end.

There's only one thing I can think of that you could try, however, I should warn you, I would not actually recommend it as it barely passes as a workaround at this point.

This would involve utilizing the SIP ID functionality along with a dummy/routing extension.

1. Go into "Settings >> Network >> FQDN" and enable Direct SIP.
2. Create a dummy/routing extension, go to the "Options" tab and set it's SIP ID to the non-geographical number.
3. Go to the "Forwarding Rules" tab and scroll down to "Exceptions". Create an Exception that matches all calls (use asterisk:* in the caller ID field) and route calls to external number. Set the number to the geographical number.
4. Save the settings and give it a go by calling the non-geographical number.

As mentioned above I can't guarantee this will work and would actually not recommend it unless an absolute necessity. Direct SIP is not designed for such a scenario and will also open your PBX to incoming direct SIP calls. This configuration will also prove tedious to implement if needed for more than a couple of numbers and will potentially also be difficult to manage in the future. I strongly urge you to check if this is possible to do on the SIP Provider's end first.

 

[leejor]

The fact that you can only strip 9 digits may indeed mean that this is not possible to do. I take it the two numbers (geographic and non) do not have common digits at the end?

Unfortunately, this limit has been in place "forever", removing it, is long overdue and would allow for complete outgoing number substitution. That would allow, not only, this type of scenario, but the replacement of a billable call, with a toll free number. Is there some technical reason, this has not changed?