Nicor Gas nicor gas, natural gas rates, natural gas plans, natural gas service, natural gas providers, pay your gas bill, natural gas pipes, pipe replacement, gas services, gas products, gas appliances, read meter, gas safety, dig safely, natural gas benefits, As the largest natural gas distribution company in Illinois, Nicor Gas ensures that natural gas – an American, abundant, affordable and clean energy source – reaches more than 2.2 million homes and businesses in an area that encompasses most of the northern third of Illinois, excluding the city of Chicago and parts of northern Cook County and Lake County.