PIERRE, S.D. (KELO) -- The nearly 50,000 customers in South Dakota who get their natural gas from NorthWestern Energy will soon be paying more. The South Dakota Public Utilities Commission on Tuesday agreed to a settlement that allows NorthWestern Energy to raise all of its rates and to increase monthly fees. For CO2 line, a thinner path may mean fewer intervene But those increases will be less than what NorthWestern Energy had originally wanted. The company asked to charge about $6 million more per year. The settlement reduced that to $4.6 million. For a residential customer using 100 therms, NorthWestern wanted to charge an additional $8.38 or 7.92%. Under the settlement, that same residential customer will pay an additional $6.47 per month. The commission last allowed NorthWestern Energy to raise its natural gas rates in 2011. “A lot of questions, a lot of clarity,” commissioner Gary Hanson said. He praised the commission's staff and the company for arriving at an agreement. “There was a lot of give and take. I’d guess there was a lot of arm twisting.”   The increases take effect on December 19. The settlement calls for NorthWestern Energy to not seek further increases in base rates that would take effect before January 1, 2028, unless there is an "extraordinary event."