Clent has a KXT1232. All stations have direct line access,two stations using XDP. Total of 7 lines, first four lines in HTG with local telco carrier and three via VOIP service. They want to restrict LD on the first 4 lines and allow on last three. Can I accomplish this with Carrier Access codes? I don't see how COS and Toll restriction would work.

I'm pretty sure that you are dealing with a KX-TD1232, not a KX-T1232(11D) since you mentioned XDP stations, indicative of the digital system.

You can do this via ARS for simplicity. Just force all 1+ (long distance) calls to a second trunk group that contains the VoIP trunks. You should allow 1+ toll free NPA's to go out over the local provider's lines though. No sense in tying up the VoIP trunks for free calls.

The customer will just have to get used to dialing 9+ for their outgoing calls and let the system programming do the routing.

If they insist on manually selecting lines and overriding ARS, just convert their line buttons to loops to prevent this from happening.

Oops my bad; its an old kxta1232. I shouldn't have used the XDP phrase. They have a computr plugged into the tel port using it to make the calls for them. I agree with your suggestion. I figured i would have to reprogram to dial 9 access and convert the buttons.
Thank you for the confirmation.