We recently acquired a customer based in the US while our operations are centred in the UK. A US number has been incorporated into our current SIP trunk. I’m exploring the feasibility of implementing a dialling feature, such as pressing 9, to ensure that the extension dials out with the US Caller ID. Otherwise, without pressing 9, we would continue to present our standard UK Caller ID.
I’m not sure how your numbering plan is set up for outbound calls on your system but if first-digit “1” does not conflict with your dial plan, just create a route for 1NXXNXXXXXX to route numbers for the North American Numbering Plan calls. We have fixed plan number length in the US and Canada. On the outbound route, assign the US number as the caller-id and set “Override Extension” to “yes.”