We are near Dayton, Oh with the heat in the 90's for an extended time with heat indicies in the 100's. Ours was $158 for 1700+ sq. ft. We just changed suppliers, which saved us $30 this past month. We keep the temp at 78 24/7 and keep the blinds closed when the sun is on them. When we renovated the house, we insulated very well with good windows. It will probably be a little higher on the next bill. There are just the 2 of us, which helps.