To true-up differences between estimated and actual natural gas costs, NW Natural filed an annual Purchased Gas Adjustment (PGA) with the Washington Utilities and Transportation Commission (WUTC) on Sept. 14.

Rates will be further impacted by a separate NW Natural general rate case filed with the WUTC last year. If approved, customers will see new rates on monthly bills starting as early as Nov. 1, according to a press release.