1. (a) Except as otherwise provided in subsections (b) and (c), and subject to the schedule set forth in this section, an electricity supplier must petition the commission for approval of any change in its basic rates and charges through the submission of a multi-year rate plan in accordance with this chapter. An electricity supplier shall file its first petition with the commission for approval of a multi-year rate plan under this chapter according to the following schedule:

   1. (1) After November 15, 2026, and before December 15, 2026, for the electricity supplier with the greatest number of Indiana customers.

   2. (2) After June 30, 2027, and before August 1, 2027, for an electricity supplier with respect to which the commission has issued an order that:

      1. (A) establishes basic rates and charges for the electricity supplier as part of a base rate case; and
      2. (B) is issued after April 30, 2024, and before February 1, 2025.

   3. (3) After December 31, 2027, and before February 1, 2028, for an electricity supplier with respect to which the commission has issued an order that:

      1. (A) establishes basic rates and charges for the electricity supplier as part of a base rate case; and
      2. (B) is issued after February 1, 2025, and before April 1, 2025.

   4. (4) After June 30, 2028, and before August 1, 2028, for an electricity supplier with respect to which the commission has issued an order that:

      1. (A) establishes basic rates and charges for the electricity supplier as part of a base rate case; and
      2. (B) is issued after June 1, 2025, and before July 1, 2025.

   5. (5) After December 31, 2028, and before February 1, 2029, for an electricity supplier with respect to which the commission has issued an order that:

      1. (A) establishes basic rates and charges for the electricity supplier as part of a base rate case that is not part of a multi-year rate plan under this chapter; and
      2. (B) is issued after January 1, 2026.

2. (b) An electricity supplier may file its first petition with the commission for approval of a multi-year rate plan under this chapter before the beginning of the time frame that would otherwise apply to the electricity supplier under subsection (a) if the petition:

   1. (1) requests approval of a reduction in the electricity supplier's overall revenue requirement for the first rate year of the multi-year rate plan;
   2. (2) meets all requirements for a multi-year rate plan under this chapter; and
   3. (3) is filed with the commission not later than September 1, 2026.

3. (c) An electricity supplier may petition the commission for relief for changes to the electricity supplier's basic rates and charges:

   1. (1) after March 14, 2026; and

   2. (2) before the beginning of the electricity supplier's applicable time frame for filing the electricity supplier's first petition for approval of multi-year rate plan under subsection (a).

      However, the filing of a petition for relief under this subsection does not exempt an electricity supplier from filing its first petition for a multi-year rate plan under this chapter in accordance with the schedule set forth in subsection (a).

4. (d) An electricity supplier shall file its second petition and all subsequent petitions with the commission for approval of a multi-year rate plan under this chapter:

   1. (1) not earlier than sixty (60) days before; and

   2. (2) not later than thirty (30) days before;

      the expiration of its then current multi-year rate plan.

As added by P.L.36-2026, SEC.10.