26 Del. C. § 300: Rate schedule and rate classifications.

(a) The Commission may require every public utility to file with the Commission complete schedules of every classification employed and of every individual or joint rate, fare or charge made, charged or executed by the public utility for any regulated product or service supplied or rendered within this State. Every application for a certificate of public convenience and necessity shall include a proposed tariff for approval by the Commission. A copy of all regulated tariffs then in effect shall be available for inspection by customers at each public office of the utility where applications for service are received.

(b) This section shall not apply to charges made for electric supply service or for transmission or ancillary services on and after October 1, 1999, for Delmarva Power & Light Company and April 1, 2000, for Delaware Electric Cooperative.

(c) Any person or entity in the business of a wastewater utility as of June 7, 2004, and subject to the supervision and regulation of the Commission under this chapter shall file a schedule of its rates in effect as of June 7, 2004, by November 3, 2004, in such form as the Commission may require. On July 6, 2004, such wastewater utility’s rates will be deemed in effect pending the outcome of an initial rate change request application filed in accordance with this title. Such application must be filed by January 2, 2005. A wastewater utility required to make such a rate filing may seek the assistance of the Commission in preparing its rate filing. Rates in effect on July 6, 2004, shall be deemed temporary and not subject to change, unless ordered by the Commission. Section 306 of this title shall not apply pending the outcome of this initial rate setting case. The Commission shall have 9 months to complete its review following the filing of the rate change application. However, to the extent possible, the Commission shall attempt to expedite such application. For good cause shown, the Commission may waive any provision of this subsection.

(d) Notwithstanding any other law, no public utility may assess switched access rates pursuant to tariff that are higher than the switched access rates set forth in the tariffs of the incumbent local exchange provider in the same service territory.

(e) Notwithstanding any other law, a public utility that provides telecommunications services shall not be subject to mandatory tariff or other filing requirements except with respect to switched access service.

(f) Rate transparency. —

(1) Each public utility shall prepare, maintain, and file with the Commission for approval, for each customer class it serves, a rate summary table for each rate class showing the total effective rate and itemizing each rate element including each base rate element; each transmission and supply element; and each rider, surcharge, and adjustment mechanism, including, statutory charges, distribution system improvement charge, and any other Commission approved rider or surcharge.

(2) Each component in the rate summary table shall be displayed numerically, using the same units in which the customer is billed. Beginning September 1, 2027, Commission regulated electric utilities shall bill standard offer service customers transmission charges in the same monthly billing determinants as distribution rates.

(3) The rate summary table shall include a schedule that identifies the components of rates that change on a predictable schedule (for example, rates that change annually) and the cadence of such change during the calendar year.

(4) The Commission may reject or require revisions to any rate summary table that it deems incomplete, inaccurate, or inconsistent with approved rates.

(5) The public utility shall include the rate summary table in the public utility’s tariff as a separate, clearly labeled section, post the rate summary table for each customer class in an easily accessible location on its website, include the rate summary table for that customer class in its customer bills, and file with the Commission and update in each of the foregoing locations an updated rate summary table at least 30 days after the effective date of any change to any component of its rates.