(220 ILCS 5/19-135)
    Sec. 19-135. Single billing.
    (a) It is the intent of the General Assembly that in any service area where customers are able to choose their natural gas supplier, a single billing option shall be offered to customers for both the services provided by the alternative gas supplier and the delivery services provided by the gas utility. A gas utility shall file a tariff pursuant to Article IX of this Act that allows alternative gas suppliers to issue single bills to residential and small commercial customers for both the services provided by the alternative gas supplier and the delivery services provided by the gas utility to customers; provided that if a form of single billing is being offered in a gas utility's service area on the effective date of this amendatory Act of the 92nd General Assembly, that form of single billing shall remain in effect unless and until otherwise ordered by the Commission.
    (b) Every alternative gas supplier that issues a single bill for delivery and supply shall include on the single bill issued to a residential customer the current utility gas supply cost rate per therm that would apply to the customer for the billing period if the customer obtained supply from the utility, including all fixed or monthly supply charges and other charges, credits, or rates that are part of the gas supply price.
    (c) Every gas utility that offers supply choice and provides delivery and alternative gas supply service on a single bill to its residential customers shall include on the bill of each residential customer who purchases supply services from an alternative gas supplier the current utility gas supply cost rate per therm that would apply to the customer for the billing period if the customer obtained supply from the utility, including all fixed or monthly supply charges and other charges, credits, or rates that are part of the gas supply price.
(Source: P.A. 101-590, eff. 1-1-20.)