Having to Dial “1” has nothing to do with who pays for the call. Calls without a “1” are calls within your local calling area, calls with a “1” are toll calls.
We have 2 area codes here within our local calling area, but whether or not you have to dial a “1” varies from to exchange to exchange, some exchanges are in the local calling area, and some are not. To confuse things further, even though I have to dial a “1” for some exchanges, they are billed as local calls.
What this all means to you is that you’re going to have to look at all of your local exchanges, determine which are toll calls, configure the system to recognize them and prepend them with a “1”.
Now…to issue a caveat on all of this, I utilize a PRI for a trunk, so what I’ve said may or may not apply to your configuration…depending on your connectivity!
BF