Local residents heating their home and cooking with natural gas supplied by Westwood-based utility NStar could save up to $15 per month over their current rates if a proposed rate cut is approved by the Massachusetts Department of Public Utilities.

If approved, NStar’s current supply price would drop by roughly 16 percent. On average, the utility said the new lower supply price will save customers who about $15 per month compared with current rates, and roughly $30 per month compared to last winter.

NStar has submitted a new gas supply rate of 58.69 cents per therm, down from the current rate of approximately 70 cents. If the proposed price cut is approved, NStar Gas heating customers using an average of 131 therms per month between November and May will pay a total of $144.68 a month, down from the current price of $159.63. For most customers who heat with natural gas, this amount also includes cooking and water-heating, the utility said.

"Along with being one of the cleanest, most efficient heating-fuel options, the continued drop in prices has made natural gas one of the most economical choices as well," NStar Chairman, President and CEO Tom May said in a statement. "While prices for other heating fuels remain high, lower natural gas prices are helping families to stay warm this winter with less of an impact on their household budgets."