With the increase in the wholesale cost of natural gas, utility companies across Indiana are warning customers to expect at least modest increases in their heating bills this winter. An average of about ten dollars a month more in the Indianapolis area, says Citizens Energy. From the western border to the east, much of central Indiana, that part of the state served by Center Point Energy North, could see average monthly bills rise from 88 dollars a month last season to 130 dollars this winter. Like the others, Indiana-Michigan Power, serving much of northern and eastern Indiana, recommends setting your thermostat at 68, not 72, and making sure you have a clean furnace filter.