PSNC Energy and Piedmont Natural Gas, the state's two largest natural gas utilities, don't plan to lower their residential prices in October despite low wholesale prices.

"There needs to be a continued level of decline," said Angie Townsend, a spokesman for PSNC. "It's not just based on several days' dip."

PSNC serves 422,000 customer in North Carolina, including 225,000 in the Triangle. After three price decreases this year, the company's year-round residential customers are paying the same price now that they paid a year ago: $1.28 per therm, a unit of heat measure. PSNC dropped its price from $1.33 a therm in March, a reduction of about 4 percent.

Since PSNC last reduced its retail residential price to account for its lowered cost of natural gas, the commodity has dropped 35 percent on the spot market and 27 percent on the futures market.

Natural gas utilities base their prices on a variety of factors. They lock in future prices out six months and more, and they factor in the prices they've paid for gas that they've been keeping in storage for winter demand. As a result, the prices paid by consumers reflect composite costs spanning months of contracts.

The utilities pass on the cost of the fuel directly to their customers. Based on its contracts, PSNC has dropped its residential prices by 26 percent this year.

Piedmont Natural Gas charges its residential customers $1.32 per therm and reduced its price in May. The company serves about 710,00 North Carolina customers, including in Fayetteville and Clayton.

The reason for the stunning dip in natural gas prices on the New York Mercantile Exchange: healthy storage levels and a quiet hurricane season, sparing rigs and pipelines from damage. A year ago natural gas prices jumped when facilities were knocked out by hurricanes.

Weather is the perpetual wild card when it comes to natural gas pricing. A hot summer drives up natural gas use by utilities, potentially reducing supply; hurricanes knock out production; and a cold winter snap drives up demand. Conversely, last year's unseasonably warm winter brought much needed pricing relief.

"Customers could see similar bills [like] they saw last year because a normal winter could drive up consumption," said Piedmont spokesman David Trusty.

Still, natural gas futures prices are expected to increase again this winter, when demand is tight. That's why the current pricing dip could be short-lived and PSNC and Piedmont are not rushing to drop their prices, which they would then have to raise again if wholesale prices rebounded, company officials said.