Least Cost Routing - How does it work?

Carrier Pre- Selection uses automated network access technology, so traffic originating from your site will be routed directly to your chosen network without any need for prefix codes. The “selection” of the preferred provider is done automatically at point of entry (the local exchange) to the public voice network.

Certain types of call are not carried via CPS, regardless of the call option selected, as they are BT services and included in the rental charges. These include calls to emergency numbers, operator assistance, directory enquiries and number ranges for flat rate Internet access (those starting with 0844 04 or 0808 99). You will continue to have access to these services and any charges will appear on your BT bill.

If you have more than one phone line, you can choose different CPS call options for each. However, all extensions on the same line must have the same CPS option.