The latest survey shows People's Gas and Nicor received among the lowest scores among large utilities in the Midwest.
The survey included more than 62,000 customers of the 75 largest gas utilities in the country.
The survey covered billing and payments, price, customer service and service in the field.
The average satisfaction score among the utilities was 627 points out of 1,000. Nicor received 592 points. People's gas was even lower at 587.
Only larger utilities were included, so North Shore Gas was not part of this survey.