The filings with the North Carolina Utilities Commission (NCUC) and South Carolina’s Public Service Commission (PSC) seek to lower the wholesale cost of gas benchmark contained within the customer billing rates in each state and reflect declines in the wholesale cost of natural gas.

The proposed reductions, if approved by the respective state regulatory bodies, would each go into effect on March 1, 2010. The proposed reductions would have the effect of reducing residential billing rates in each state by approximately 5% from their current levels and between 5% (South Carolina) and 10% (North Carolina) from billing rates of a year ago.

The benchmark reflects the wholesale cost of natural gas supplies purchased by the company on behalf of its customers and can fluctuate up or down. The wholesale cost of gas represents the single largest portion of a residential or commercial customer’s monthly natural gas bill, typically making up between 65% and 70% of the total bill, the company said.

As a regulated natural gas distribution company, Piedmont Natural Gas trues-up or passes through the wholesale cost of gas to its customers on a dollar-for-dollar basis.