Officials from Mass. order lower gas prices. Here is how much

Brutally cold temperatures will hit New England this weekend, forcing residents to turn up their heating. Fortunately, most people who heat their homes with gas will pay less this month.

The Massachusetts Department of Utilities announced Thursday that it has approved gas supply rate reductions for customers across the state. Overall, monthly bills will decrease by approximately 4-5% for an average home heating customer.

The changes went into effect on Wednesday. They are the result of “the evolution of the market-based price of natural gas over the winter period,” officials said. The lower rates will be reflected in the utility bills residents will receive in March.

“Our administration is focused on reducing costs for Massachusetts residents and businesses,” Governor Maura Healey said in a statement. “We are exploring all possible tools to lighten the load, energy cost reductions, fuel assistance, nutritional support, etc. With these reduced energy prices, small businesses can grow and more families will be able to put food on the table and roofs over their heads.

The changes will affect customers of The Berkshire Gas Company, Liberty Utilities, Fitchburg Gas and Electric Light Company (Unitil), Boston Gas Company (National Grid) and NSTAR Gas Company (Eversource Energy).

Gas distribution companies such as these are required by law to purchase gas at market price on behalf of their customers. Gas supply rates are the costs of actual gas burned in residents’ homes, and utility companies pass the costs directly to customers. The DPU obliges these companies to adjust their gas supply tariffs if prices on the open market fluctuate significantly.

In most cases, the supply rate changes twice a year. But if there is a large fluctuation in the market that causes utilities to over-collect or under-collect money from customers, the DPU can order a supply rate adjustment. This is what just happened in Massachusetts.

Supply rates change at least every November 1 and May 1, but falling natural gas prices in the competitive market are forcing companies to lower their supply rates for gas consumed between February 1 and April 30 .

“This reduction in energy costs is not too soon for struggling Massachusetts residents,” Energy and Environmental Affairs Secretary Rebecca Tepper said in a statement. “But this adjustment is also an important reminder that we must urgently and fairly transition from volatile fossil fuels, which continue to threaten the financial security of our communities. The Healey-Driscoll administration is moving quickly to build a clean energy future to reduce costs and support our businesses.