NOTICE DATE: December 19, 2025
NOTICE TYPE: M-A121925-01 Operations
SHORT DESCRIPTION: 2026 Minimum Monthly Ancillary Service Requirements
INTENDED AUDIENCE: ERCOT Market Participants
DAYS AFFECTED: January 1, 2026
LONG DESCRIPTION: On September 23, 2025, the ERCOT Board of Directors recommended for Public Utility Commission of Texas (PUCT) approval the 2026 ERCOT Methodologies for Determining Ancillary Service Requirements ("2026 AS Methodology"). On November 6, 2025, the PUCT approved the 2026 AS Methodology. The approved changes modify the methodology for determining minimum quantities for ERCOT Contingency Reserve Service (ECRS) and Non-Spinning Reserve (Non-Spin) Service. The methodology for determining minimum quantities for Regulation Service and Responsive Reserve Service remains the same as the 2025 AS Methodology. ERCOT's September 23, 2025, presentation to the ERCOT Board of Directors provides additional details about these changes. The 2026 AS Methodology will be effective beginning January 1, 2026.
ADDITIONAL INFORMATION: Per the 2026 AS Methodology, the minimum monthly Ancillary Services quantities for 2026 have been posted in the Ancillary Service Requirement Methodology report (EMIL ID NP3-783-M, Report ID 13036) on ERCOT's website. The posted quantities reflect minimum requirements only. ERCOT will follow-up with a Market Notice if any upward adjustments to these minimum quantities are made.
Note that the 2026 AS Methodology sets the minimum capacity required from Resources providing RRS by using Primary Frequency Response to 1,377 MW. This updated limit will be effective beginning January 1, 2026.
CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at ClientServices@ercot.com.
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